Is there any way to zoom/collapse the grid vertically to get an overview of the note pattern and avoid scrolling up and down endlessly?
currently no, but i think there's value in this being explored at some point.
see if a suggestion has already been made to upvote at https://forums.synthstrom.com/categories/deluge-suggestions or make your own thread if there isn't currently one.
in ableton there is "flat" function, could be adopted?
Yeah, that would make life so much easier