It does not. Any example where 1px is not equal 1px? It’s just somewhat convoluted:
Simple things like lacks of auto scale to original size (am i doing something wrong?)
Scale Box? Other than that, not sure what you mean.
You have to clear colors, because tint makes it darker? like why man
Not sure what you mean. Any examples? Are you getting widget components involved? Or retainers?
Overall bad for performance
Hm. Any examples of it underperforming? There is a TON of optimisation that can be done; if you’re going to Tick 1000 widgets with complex hit-testable hierarchy and transparency, you’re going to have a bad time (in any engine). Never bind functions unless you want something updated every frame - this is a major bummer that is tought in 99% of all tutorials…
It all depends on your needs. Search the Knowledge Database for widget optimisation, there’s some good reading in there.
Anyway… Any Alternatives?
No. Well, yes. Write your own stuff in Slate, and then expose to UMG, but then you’re using the bad widgets again. 
There’s also the venerable HUD class but you will not like it if you do not like UMG. It can be blazing fast when used right and offers some unique functionality. But it’s a bit apples vs oranges. They have little in common bar showing 2d stuff in viewport.