If i may put my 2 cents in…
I would like to see an overview window that allows you to view your patterns in the sequencer from end to end. Does not have to be highly detailed, just a window where you can get a global view of the whole project.
This way you can listen and view at the same time, with an immediate sense of what changes you want to make. This would really help you to get your head around a whole tune.
Blessings,
Damon