-I don't have any issue with the menu, maybe that's a web build thing?
-yep, some enemies have too much hp or they stay on the screen for too short
-the lives displayed are revives, you can have 0-4 of them and at the start you get 3, you lose when you take damage with 0 of them
-yes, I agree, the game isn't polished enough
-yeah, there are quite a few safe spots, part of them in the middle
If I had more time or just coded more efficiently I could add and fix so many things, including more difficulties and more stages.
Thanks for feedback, I already started planning a full remake of this game so it's appreciated :)