I think I own the best midi controller ever made -- the Peavey C8. It has 2 wheels and 4 sliders, put plenty of pedal inputs for CV or switches. I use the power... in my opinion, using a wheel for articulation choice is not always musical. I tend to use keyswitches for articulations, and the wheel for vel x-fade. So having 2 wheels is very flexible. I am still on the fence re: the breath controller -- I saw Paul demo it and he really was able to do some very expressive performances with it. But I have been able to use wheel2 to my satisfaction, so not sure if I would get any benefit from the breath controller for non wind instruments.
Why would you use the wheel for legato/port for solo strings? Assign that to a keyswitch. Way more musical, if you ask me. I do not use the pre-built matricies, I am rolling my own, as required for my work. So simply build up what you need, and use the controllers that are most intuitive for you. If you like A/B for the App strings, then why not use C1/C#1 for Solo legato/port
I have only been using the library for about a month - but quickly learned a good workflow for myself -- use the preset matricies as a learning tool, then modify them for yourself. So instead of using controller 1 for , make it a keyswitch.
Another thing I learned: keep your matricies as simply as possible. If you only need a 1 cell patch, then give it its own keyswitch and move on. Trying make the ultimate matrix was a time zombie for me. Once I accepted that there was more than a few ways to build up the patches, it really helped my workflow. You have plenty of options. Don't feel you have to use the factory matricies!