I have encountered a simple problem that has not been in the drum editor for as long as I have used Cubase (since 5). The problem is with the drum editor diamonds having the actual “hitbox” that they occupy visually rather than being triggered by a square hitbox. Before Cubase 9, the drum editor would delete the hit if you pressed on the general square that the diamond is inside of (think flipping the red diamond 45 degrees) whereas now you can accidentally stack multiple hits on top of each other if you miss the actual visual red diamond image. This makes drum editing a lot slower for me.
I can see the benefits of this so I’m suggesting an option to circumvent this, either by a simple checkbox that disallows multiple stacked hits in the drum editor window (thus deleting the old hit if the space you clicked was occupied by a hit) or by having an option to revert back to the old workflow some other way.