I was very impressed with Waveform too, and was tempted to pick up a license just on principle because I feel like it's got so much potential and momentum. There are so many good options right now... But there a lot to like in Waveform for sure.

I think my first 'sequencer' was the memory function on a Casio PT-1... But that hardly counts, even though a friend and I had a ton of fun programming a pair of them to play the left and right hand parts of Bach Two-Part Inventions and trying to start then in sync... Then I went vintage before vintage was cool and played nothing but a Rhodes, a Moog Rogue and a CS80 for a few years. Then the was an Ensoniq SQ-80 which got me started on sequencing again. Finally a Kurzweil K2000 and an early version of Cubase...

This was a great program for the time.
 
Recently deleted DOP from my storage because it will not run on anything past win XP, if I am correct. May only apply to the Pro version because of the audio inclusion.
Voyetra was one of my first happy encounters with online activation. They shut down the activation server with the excuse that they were protecting me against old software, so they made the decision to stop any license transfer or new activations. That disclaimer is probably still on their website.
 
No vst/vsti support, but was one of the most powerful quantitizing editors for drums. Was perfect for loop creation. You did your sketches with windows midi wave table and exported the mid files to your drum machine of choice.
 
For what it is worth, the upgraded Midi Orchestrator is still out there on the internet. It installs on win 10 without problem and has all the features Digital Orchestrator had plus more. I still use it on occasion.
 
John

Got my first sequencer in the mid-90's, and it was a hardware unit, Alesis MMT-8.  From that one, moved up to a Korg X2 workstation with on-board sequencer.
 
But I found pushing a cursor around a small LCD screen by pushing buttons to be a mind numbing task.  It worked, but there had to be a better way...
 
So one day I was looking over the new gear at my local music store (we still had those back then), and I noticed they had set up a demo with a Mac and MOTU Digital Performer (I think that is what was running that day).  Well that gear was way above my pay grade, but the impression stuck with me.
 
So after I acquired my first Windows PC (Pentium 1 - 133 MHz - 16MB RAM), I picked up Digital Orchestrator at my local Computer City store (we still had those back then, too).  Didn't know anything about computer music yet, but that was my first encounter with computer sequencing.  And then promptly learned that I would need a full duplex sound card, because that onboard sh*t just didn't cut it.  Cue up a Creative Sound Blaster! 
 
I learned about computer recording, and even attempted recording a song that my buddy wrote, for acoustic guitar and vocals.  The program was nice in concept and features, great with MIDI, but turned out to be a bit unstable with audio in my PC, to say the least.  It ate a weekends worth of audio takes, with no apparent recovery possible, ugh!
 
So I started asking around about music software for Windows.  Somebody in a computer store suggested Cakewalk, and so that is how I ended up with Cakewalk Professional, then upgraded to Pro Audio.  And that was a good 20 years ago! 

After some browsing I think Anvil Studios might be my next sequencer. But I will surely check out the other software mentioned. Also, since I still have some ORC files (the file format of late Voyetra Orchestrator) I am giving "Record Producer", also from Voyetra, a try. Actually seems to run on Windows 10. Now, obtaining a license might be tricky. It is as dead as DOP...

 I still have DOP but when XP came out they never bothered to upgraded it.

Pasi Sivula
So, what tool should I be trying out if I want to focus on quick and effortless midi composing on Windows 10 with a feature set resembling that of DOP and not tons of bells and whistles. I particularly dislike tools like Garageband, without being able to put my finger on why. I need no crazy advanced arpeggiator, sound libraries, soft synths etc. But the user experience has to be top notch. No unpolished, mediocre, opensource stuff that will drive me crazy to set up with my hardware. Thanks

I would say take a look at Tracktion T6, full version DAW for free, company is still in business! 
 
A little history behind this company is that they were acquired by Mackie shortly after they began, who distributed their product for a while, but eventually let it linger in neglect.  It rose from the ashes when it was re-acquired by the original developer and the Tracktion Corporation was born.  So I'm sure they have plans to stick around.
 
Just register for free account to download. 

 
The world's best, fully featured, completely unlimited free DAW for all music creators
 
This is no ‘Lite’ version, we do not impose track limits, plugin limitations or other such constraints commonly found in other low cost offerings. Why? – we think you will enjoy using the app so much, you will discover the value in investing in our latest versions and the expanded features we are voraciously adding. Innovation and creativity is what drives us – join the ride today and download T6 for Mac, Windows, or Linux operating systems.

 
https://www.tracktion.com/products/t6-daw
 
Tutorial videos:  https://www.tracktion.com/training/videos
 
Unlimited tracks, VST support, and much more.  Single window interface with inputs on left, track clips in the middle, outputs, effect bins and mixer settings on the right.  Uses one type of track that will hold any objects such as MIDI clips, audio clips, etc.  Inline MIDI editor.  This program would function as a nice MIDI sequencer/editor.
 
I also use the latest Tracktion product, Waveform 8, which I got before Cakewalk went under to use as a secondary DAW.  This version has added an optional separate mixer window, separate MIDI editor, and some MIDI pattern generators that can add to the creative inspirations.  But you really could do everything needed in a sequencer with Tracktion T6.

TheMaartian

Pasi Sivula
So, what tool should I be trying out if I want to focus on quick and effortless midi composing on Windows 10 with a feature set resembling that of DOP and not tons of bells and whistles. I particularly dislike tools like Garageband, without being able to put my finger on why. I need no crazy advanced arpeggiator, sound libraries, soft synths etc. But the user experience has to be top notch. No unpolished, mediocre, opensource stuff that will drive me crazy to set up with my hardware. Thanks

I never used DOP. That said, if I hadn't already been so invested in Studio One Pro when SONAR folded, I'd have given Tracktion Waveform a real shot. I'll always have Reaper as a secondary DAW, but it definitely does NOT fall into your easy-to-use out of the box requirement.
 
Waveform is modern and focused on music production, kind of a lean, mean, fighting machine. Ha. They have a demo. I think it would be worth a try.
 
https://www.tracktion.com/products/waveform
 

I really like Waveform, but rather than demo that for starters I would suggest Tracktion T6, with less bells and whistles.  Full version for free!  The MIDI editor is inline in the track clip in T6, but the track can be expanded to show the piano roll for editing.
 
For MIDI folks, the main new feature in Waveform that is not included in T6 is the separate MIDI piano roll editor that can be docked/undocked, resized, moved to a 2nd monitor. 

Pasi Sivula
After some browsing I think Anvil Studios might be my next sequencer...

Good lord, why? I had a 30 second look at the website. There is no reason to trap yourself in 1995.

Follow the good advice here. Get Tracktion T6. It's a proper DAW/sequencer, modern and relatively full-featured but easy and approachable, and free.

Back for a minute to the Voyetra programs, Record Producer should load in win 10, but as advised, will be the greater chance of finding a snowball in the brimstone pit than obtaining a license. Even if you purchased it like I did, Voyetra will not allow you to activate it. You bought Midi Producer or Record Producer and Voyetra threw the middle finger at you after getting your money. Midi Producer went on a campaigned fire sale for 12 dollars, trying to get the last penny from victims a couple weeks before shutting down the activation centers. Funny how they never advertised that part of the agreement. Strangely reminds me of another program sucking in buyers with promises of lifetime upgrades before dropping the bomb.
 
What Record Producer brought to the table for the time was 32 bit architecture in the audio realm, really cool but before the time that vst format gained ground and became a necessity. This is why 16 bit Digital Orchestrator Pro will not load in win 10 (just pulled it up to try it again). Bummer because DOP only needed a serial number, and it is the audio engine associated with the midi part that kills it on a modern OS.
 
Even if you could get RP running and authorized, there is no support for vst/vsti plugins, so doubt anyone would want it for a primary DAW. Audio did work well.
 
Stripped of the audio function, Midi Orchestrator had all the guts of the midi machine and came with an impressive library of drum loops, but many in the rpms or whatever format which could be converted to mid files from the program, but nothing else opens them up unless converted.
 
MO came as an individual purchase, or as a freebie if you bought their midi to USB cable..
 
Still a stellar loop monster in my opinion. The way it sections off discrete blocks of measures and a killer quantitize function. All the overdub or replace stuff as options.
 
I have the abandonware program without any need for online activation. As much grief as those guys caused me, would be glad to share the bounty. Got it stashed somewhere around here. Main use would be loop creation written upon the windows wave table GM format, exported as a midi file, imported into Reaper or whatever.
 
Welcome to PM me if you want to try this.
 
John

Thanks for all the advice. I feel like I stole the thread from OP:s beautiful post so I will ask no more.
 
Some final words, though: I thought I was alone in using the niche Voyetra software back then. Lots of friends and acquintances that would reject it without even trying it, always referring to Cubase and the like. Of course Cubase, Steinberg, Cakewalk and the sort were more advanced and more useful for the PRO, ... but I was never a PRO. I needed software that kept composing a lot of fun and to me that would be software that I could use to capture the melodies that popped up in myhead in the fastest and easiest way. If it had not been fun, I would have quit earlier. I have some 300+ songs in my archives that would never have been created without DOP. I even had a small fanbase on the still young Internet and I recall it as a very fun period in my life. Had it not been for the music I would have been playing computer games instead. Anything to avoid studying for the next exam...