As an X2 user who came directly to X2 from 8.5, let me say this: X2 was a big step forward from X1, but there's still room for some major workflow improvements:
1. The GUI feels bigger. The mixer channels in particular, but even the main inspector (global toolbar).
2. The size of the mixer should scale when docked. For instance, if docked at the bottom or the top, I should have access to the full length of the volume fader, a pan pot, and the Mute/Solo buttons.
3. I'd like better effect to effect navigation (like Studio One and/or Logic) where you can be in one channel's effect and jump right to another effect in that channel directly from the plugin menu.
4. I'd like instrument to instrument navigation from the plugin menu too.
5. Better routing. I'd like to feed an audio or instrument track's output to the input of another track. Any audio out should be able to be routed to one or more audio ins.
6. One pass bouncing on multi-output instruments. If I have a 16 out Kontakt score and want to freeze it, Sonar does 16 bounces. It should do 1. I don't have that much time to wait for it to bounce. Same for something like BFD2.
7. Make Snap more intuitive. The interaction between the PRV Snap, the Global Snap, and the Event Duration items has created some confusion. I see what you guys are trying, but it's still too hard. I need to be able to use key bindings to change Snap lengths as well as event durations.
8. I need to open the "Track Template" folder to see Track Templates in the browser. I'd just like them to appear as an option like VST effects/instruments without having to open a separate folder. Same should probably be done for FX chains.
That said, there's some big plusses. Just off the top of my head:
1. Love drag and drop instruments/effects (might have been an X1)
2. Love, love, love keysets. These make up for some of the shortcomings about the large GUI.
3. Can't get enough of the Smart Tool
4. Full screen mode is fantastic
5. The step sequencer, arpeggiator, and matrix view all seem much more usable now
6. Aim assist feels obvious in hindsight, but was a well thought out addition
7. Consolidated Preferences and menu items based on the view were also nice touches
8. Don't know how I lived without the FX Enable/Disable button before
9. The ability to copy screensets from other open projects was also sweet
Anyway...a nice upgrade though there's always room for improvement.
Hopefully this post helps the OP, and maybe even Cakewalk.