It would be really good to see some more usable/useful/logical tab order here and there. Specifically, try something like ReaEQ: click in the frequency input, type something, and press tab. Foom, you've (probably) got the "Add" button focused (if ReaEQ is stuck in the FX chain), or the "+" button focused (if ReaEQ is floated). Would be just lovely if focus could go to the next input box. I'm sure that letting users define tab orders in such instances, indeed in many places in REAPER, could get horrifically complicated. I admit, I only really use tab to move through fields on property windows like FX, media (and multiple) item properties, quantize, etc. So if it could be implemented for such cases, that would probably be most useful. (You'd think stuff like item properties was pretty logical as-is, but I find it confusing. Sigh.) Many thanks!

my pet peeve is when adding fx - you tab to the text filter box, type 'kont' or whatever, then have to shift tab back to the results list and arrow down to the desired plug...

@ semiquaver: that's definitely a valid instance (would be good to see tab go from filter -> list of matching plugins -- but configurable order is best!). HOWEVER, I should note that this gets embroiled with the issue of "focus" generally, and where it is passed after certain things happen. This is mentioned here, though the original issue behind the thread and its title don't really reflect the general problem:

re: focus yes dependable and sensible passing of focus would be a great improvement. It might also be helpful perhaps to have some visual indication of focus (Renoise uses little red corners on the windows) and actions to change and/or cycle focus... Another of my pet peeves is that in the main window, either tracks or items have focus (ie 'delete' will remove either tracks or items) - totally impossible to tell which at any given moment in my experience...

For similar timeline context-confusions, see this thread! Again, sort-of hijacked. You can probably tell, this kind of interface stuff is important to me. :-) Possible solutions: heaps more actions, splitting the scope down to lowest common denominators (with the ability for wider-scope actions as well), and more actual contexts (e.g., timeline, ME, TCP, FX chain, FX browser, etc.). Mad configurability ftw.