So far I'm really liking a lot of things about Studio One here.  The main things that are a miss for me are:
 

• Sound on Sound Recording
• Drum Maps

 
Aside from those, there actually MANY things that I'm preferring.  It seems generally more responsive, recognizes and uses most of midi devices/control surfaces better than Sonar did - and is easier to tweak than ACT ever was - EVEN with an Edirol PCR-800, which should have been FAR easier in Sonar than S1 because of manufacturer at the time, yet isn't.
 
Granted, I've been mostly getting things setup, playing around with proof of concept stuff, and haven't really gotten into a full song recording or mix yet, but I like a lot of what I've seen.  So much so that I purchased with the Sonar Crossgrade pricing just before the end of the year.
 

• There is Less stuff on screen in many cases, but I'm not sure that's a bad thing.
• The Prochannel never really enamored me because it always felt like the modules were all integrated into one thing, but they were all so small (except for the EQ) that they felt limiting.  In S1, the Fatchannel takes care of many of the the things I typically used the ProChannel for anyway.  I would usually have a Reverb on a bus, so no real point to the Breverb and the Comp, EQ, Limiter and Gate cover the normal things I would expect in a channel strip.  But I really only need that strip on SOME things, anyway.  And it's not like you couldn't just put it in your template anyway.  And it takes like two seconds to drag it onto a track.
• There seem to be a LOT of Sonar bugs from days gone by and many "removed" features in the X1,2,3,Plat series.  I liked the IDEA of what they were trying to do, I just feel like they missed the mark with the whole thing.
• Being a "web guy" I thought I would really dig into the Theme thing, but it was so complex and convokuted to get around, it was just a huge waste of time for me to try to use it.  I think that S1 could use a little attention in the GUI side of the house, but it's not like it's ugly or in-adjustable, and I have found much of the simplicity of the display, while still being modern, flat, and just usable to be a good step in the right direction.
• MACROS!  OMG.  There are a LOT of things that you can do with Macros in S1, I've found.  Even just some simple things, but there are already so many in place, and they are drag and drop to create.  Create a combination of commands to be executed, assign to a KB command, and Bang you just modified default behavior.  I got my Contour Shuttle Pro working for "shuttling" from beat to beat instead of measure to measure in S1 pretty quickly using macros, where in Sonar it was a weird and fiddly thing to do with CAL scripting - and I come from a development background.  The Macros are really cool.

I'm sure I will uncover many more things that I don't like, but I'm trying to "move on" and I haven't opened Sonar in a while - once just to make a video of what exactly sound on sound is for the S1 people to understand.  I enjoy change, and as a hobbyist, it's not really affecting my line of business is any way, but even in my actual business life, I'm pretty open to change of the systems I use on a daily basis to get my job done, within reason or at least with purpose.
 
Kind of a longer post than I expected, but there are just a FEW of my thoughts.  I will likely write a Blog about this experience.

A drum editor is already a feature request with a lot of votes over there, so I voted for it, explained what I also wanted, and also linked to the video I created about sonar drum maps years ago to show their value. I think it is in the top 10 of votes for the fr list so I am hopeful.