As I use it today, X2a is more than adequate for my needs.
My niggles (since X1) are:
1. Full Color Customization
2. Nested Folders
3. Fix the hokey way you must solo a single drum track when drum maps are used, I refuse to use drum maps until this is fixed. Drum maps would be soooooooo helpful to me since I have so many drum players that have fixed key mappings that DO NOT match up.
My real wishlist is a true gapless engine, as that is the only time I can make X2a crash on purpose (i.e. try inserting a UAD plug while track is playing....KA-BOOOM****)
****Ya, I know I'm not supposed to do that but 1 out 25 times I forget.
Anywho, due to tight finances I would only get X3 unless a true gapless engine was introduced and even then I may need to wait a month or two.