hello,
i think we can consider widescreen something of a casual equipement by now so i was thinking wouldn’t it be great to have the instrument list replace the advanced pattern editor operation tab, because the instrument list on top right corner is a bit small atm.
or instead of replacing it it could be merged with it, anyway to make the instrument list bigger and use the widescreen space to the best 
anyway you got the point.
I think that renoise’s GUI can be enhanced in many aspects by minor changes. One of these can be what you desire. I hope such changes will be implemented in further versions.
edit: I like the current GUI of renoise, yet I wish it was more flexible and customizable, and of course it has the potential. I discussed some changes in this thread times ago.
i really like the "one-window"style gui renoise has,and love how easy it is to switch between pattern view,mixer view etc
but im also for the gui to be more customizable(think reaper)