In the mod menu, I think half time and double time should be replaced with player definable rates, increasing the score multiplier by a non-linear value relative to the rate input.

A mock-up picture of how it might work.

There may also be a nightcore checkbox for those who prefer it!

I believe this to be more appropriate for osu! than having solid 1.5 and 0.75 song rates. (double time and half time)

The multiplier formula could be adapted to make the specific values worth what they were originally (1.5x rate = 1.12x score, 0.75x rate = 0.3x score), so that old ranks are not changed.

A mock-up picture of how it might work.

There may also be a nightcore checkbox for those who prefer it!

I believe this to be more appropriate for osu! than having solid 1.5 and 0.75 song rates. (double time and half time)

The multiplier formula could be adapted to make the specific values worth what they were originally (1.5x rate = 1.12x score, 0.75x rate = 0.3x score), so that old ranks are not changed.