I need help. I'm currently trying to make a fun platformer on scratch, but after seeing people comment on platformers with bad level design, I got nervous(Sonic 06 and Sonic Boom ). So how do I make a cool platformer without It being a disaster to play?

I can't see these other 2 platformers, but a good start to get going is to possibly make your player sprite a perfect circle. That would make things a lot better. I don't know much about platformers as they are quite difficult to make (good ones).