In general, I would like to see more options to customize Renoise.
I would like that all is better, makes more fun and is double fast as now.
No offence. But could you be a little bit more specific ? 
I mean like option to hide clock, and option to show file sizes on diskop and so on…
I’d prefer that you would going on the Sampleeditor a bit. Undo, Convert to mono, Amplify the Sample itself options etc… (thats stuff what was mentioned thousand times )
But I know your todo list is loooooooooooong 
while there are some minor small changes in the sampleeditor which really should be done (like resampling, channel converting and so on), I would much more like to see a simple windows clipboard support, because I have 2 monitors and can run cooledit in one and renoise in the other … 