Lifetime Platinum...tried to use and understand melodyne, woeful results lol...It got me wondering, why on earth didn't Cakewalk bundle a dead simple 'grab a knob, grab an interval' way/plugin/etc to instantly audition harmonized  guitar lines, etc with 'knob preset' intervals with a sort of Eventidelike H9 guitar FX processor or Kempers superb pitch shifter sound quality? I HATE trying to use melodyne. I want quick 'grab an interval knob' and go thing...

Your complaint is yet another request  of  the millions of features that someone thinks a DAW should have. Everyone of those add ons costs someone money. 
Melodyn is a little complex and ya, it's not a simple way to create a harmony. Actually the simplest way to create a harmony is--- sing/play it yourself, and then use melodyn or V Vocal to fine tune.   
 
Good Harmonising stomp boxes are not cheap, There a certainly lots of software alternatives and if you look there might even be one for free. 
 

Because that simple knob would suck worse than your "woeful" results with Melodyne.  Harmonization that's realistic is difficult.
 
If you want to "audition" harmonies on audio material you could theoretically copy the track and then transpose it.

The Eventide H3000 Factory would be a better solution for what you want to do. It's definitely not a one knob solution but it has lots of presets. Melodyne has a learning curve but it's worth the effort.
 
Rocky

Melodyne Editor has snap to scale and all other kinds of cool stuff. Ultimately, though, nothing will sound better IMHO than playing the part. i experiment with Melodyne to create the harmony, then I learn it and play it.

Have you given a gander at the FREE pitchproof intelligent harmonizer vst?
 

guitz
Lifetime Platinum...tried to use and understand melodyne, woeful results lol...It got me wondering, why on earth didn't Cakewalk bundle a dead simple 'grab a knob, grab an interval' way/plugin/etc to instantly audition harmonized  guitar lines, etc with 'knob preset' intervals with a sort of Eventidelike H9 guitar FX processor or Kempers superb pitch shifter sound quality? I HATE trying to use melodyne. I want quick 'grab an interval knob' and go thing...

Try hooking up a mic through the H9 or Kemper and let us know how great you think the results are.
 
You can buy an Eventide Plugin.  Many guitar players (including myself) rely on stompboxes for such effects, the mass appeal for a plugin (think about pitch shifting a micd amp....terrible idea) is limited to people that really work "in the box"
 
Few people outside of guitar players use harmonizer pedals/plugins, and melodyne is top tier for Vocals.
 
 

The Kemper (when I had one) had the most incredible intelligent pitch shift, especially on bent notes, just amazingly high quality...I still want a software plug-in that I don't have to dicker with like with melodyne...just give some software knobs and I'm good to go lol. There's something to be said for 'quick' flipping between intervals when writing/noodling/jamming where you may suddenly hear an amazingly cool blend that is just way too tedious with melodyne or playing manually.

bitman
Have you given a gander at the FREE pitchproof intelligent harmonizer vst?
 

I have not but will check that out, thanks

Not being a music theorist, Melodyne is a wonder for me for vocal hamonies
I often take the melody, raise it a 3rd or 5th and then play with it until it sounds good as a harmony and then I have something I can sing along to.  In the absence of someone who knows what they are doing writing harmony, I find it very useful.
I usually do not find anything usable just simply raising a third or a fifth, but once I have moved the interval I can then move blobs around until something sounds good.  
Finally, I crank the melodyne harmony track up in the mix and then sing along with it like it was the melody and the results have been quite impressive. 
 
JR