This would potentially be extremely difficult/impossible depending on how osu! is coded when it comes to map playback.
The suggestion is being able to play the game say, fullscreen at 1920x1080, but be able to adjust the 'play area' to be a % of full size
ex. Right now, the play area is approximately as seen below (100%)
I would love to be able to shrink it to say 90% of it's size to move notes away from the top/bottom edges
Relative size comparison of 90%
Some could argue this would put notes closer together, but so would simply playing windowed at a lower resolution, so that's moot.
The suggestion is being able to play the game say, fullscreen at 1920x1080, but be able to adjust the 'play area' to be a % of full size
ex. Right now, the play area is approximately as seen below (100%)
I would love to be able to shrink it to say 90% of it's size to move notes away from the top/bottom edges
Relative size comparison of 90%
Some could argue this would put notes closer together, but so would simply playing windowed at a lower resolution, so that's moot.