This actually reminds me of my first few games so much it's crazy! if I had to give you a few bits of advice, It'd be:
a) To make the player move with the moving platforms, it's actually really simple. All you need to do is when the player is on top of one of the platforms, set the player's "transform.parent " to the platform that it's on and all the movements of the platform will also happen to the player.
b) If you give yourself some more restrictions for the art (like limiting the color palette to 8 colors for the entire game for example) you'll find that everything fits together a bit better and it'll help you get better at art too. An example of this is the player sprite that you made, it just about only uses colors already used in the game so it fits well, whereas maybe some of the flowers stick out a bit.
c) Keep enjoying yourself when you're making games, I like the freedom of thought that comes with newer developers, and it so often gets lost as people fall into the box of game developing.
Anyway sorry for rambling, but I hope this helps! A solid game!