(English is not my native language, so expect errors)
Hello Max! It's a very promising project and I had an idea for Maya's costumes.
Looking at the existing costumes in the game, I noticed some analogies between them and two elements - earth (green outfit) and air (blue outfit), because in a green suit Maya bounces off the ground and can break a fragile floor, and in a blue one she can stay in the air for a long time. Based on these similarities, I thought of two more power-ups:
Red (fire) outfit - Maya can double jump in light form by a fire blast and do long rocket dashes in heavy form, similar to the Crystal Heart from Hollow Knight.
Dark blue (water) outfit - Maya will be able to make short dashes in light form (as in Celeste) and roll in heavy form.
Finally, I want to ask you to make sure that Maya, using an air suit, does not completely deflate after using up all the air designed for flight.
I hope my ideas were helpful and we will see a great platformer in the future. Good luck in development!