Bloodstained: Ritual of the Moon feels great with a 25% move speed increase (there's a mod for it).

In the base game, doing a slide or the backwards dash (both of which you have from the start) gives you a roughly 25% movement speed boost with start and end lag, but I'm not a fan of having to carefully time button combos forever to maintain top speed while backtracking in a metroid/iga-vania. The 25% speed increase takes a lot tedium out without nullifying the point of any of the later unlockable movement tech/abilities.

The only "bug" with the increased speed is that you can unlock an early game warp point early if you make what feels like a pixel perfect jump, but it doesn't significantly change anything to have it early.