If were talking about Reaper changes I think his wraith form might need a slight boost to movement speed just to help him get out of dodge a bit easier considering how fast paced matches are these days. I can't say that doing anything else to it would be
Also, just get rid of his teleport. Its objectively useless. As a Reaper main I can safely say that some of my best matches I've ever had I never used the teleport not even once. Its far too obviously telegraphed to be of any use as a flanking tool. Not to mention, its incredibly finicky to use, as its control the weird little teleport cursor ring is horribly imprecise. At least that's what I'v found to be the case on console. I can't speak for PC. He needs something that can better get around the map that doesn't take ages to use but is still somewhat telegraphed enough to at least be punished for poor use.
I'd like to see his teleport to act like it does now but a lot faster in its animation speed. But it would be a lot more quiet, with his voice line not sound like its being shouted from the heavens. The trade off being that in the direction that he'd teleport a visible trail of black smoke/mist would lead to his destination and would linger for a short time. Allowing enemies to gauge where a reaper might be to pursue him without completely screwing over Reaper as he'll have some time to widen his distance from where his teleport landed him.
Reaper needs the teleport or his ultimate becomes too predictable.