PRV track list should use/follow track scenes just as the console can. When working projects populated largely by Virtual Instruments, this list can get very messy.
When you want to edit one instrument while certain other instrument notes are visible, but not editable (Eg. Violin against the rest of a string section), this becomes cumbersome. Lots of scrolling and clicking for something Studio One has essentially already solved with the Track Scenes feature - it just doesn't apply to the PRV yet.
As a potential and hopeful Sonar immigrant, I would add that Sonar also has an 'auto lock' feature in PRV, which was very useful. While engaged, any track you select becomes the only editable midi track. It makes it very quick to edit a particular instrument against whichever other tracks you want visible.
Autolock useage example:
I could simply select my 'Strings scene' -> Now only strings are visible in PRV track list -> I just click Violin 1 and edit it against other strings (without altering them).
Even a simple 'auto lock' would save so much time, and make the 'link track selection' feature more useful (in regards to this problem).