So, who is the best superhero?

Silly question, obviously, but: We're decorating our son's nursery and amongst the pictures on the wall I figure I can squeeze a superhero in there. This will be his "first" superhero. He will have matching toys and outfits. Question is: Which one?

Batman is obviously cool, but baby batman outfits usually look rubbish as his outfits in his cooler incarnations are quite complex. Flash has nice simple costume but is a bit rubbish.

So, I'm looking for a hero who is cooler than The Flash, but easier to dress as than Batman. Thor is one option, any other suggestions?