Only one I have trouble making out is the one between Fantastic Four and Deadpool (assuming). Also the Avengers one in the bottom right corner took me awhile also so maybe add more INSIDE the design. But I love this a lot. You fix those those two and it'd be a buy from me.
I like having some of them more subtle/puzzling... if they were all super obvious it might take away from the design and just look like comic book store merch.... but thanks!!
The yellow one you're referring to is Batman btw :D
Yeah I can see you leaving the Avengers one as is, but I really think you need to add like a black bat or something to fill in the Batman one. I wouldn't have guessed it. Superman's diamond, the two D's, the Skull shape, all easy enough, but a sideways yellow oval is tough, considering unlike the others, Batman has MANY different logos. The more recent don't even have the yellow around it. Just the bat symbol. Maybe fill it in the way you did the X for X-Men. just a suggestion.
The yellow one you're referring to is Batman btw :D