It doesn't seem to have hurt Spiderman movies to have different characters play the role... BUT none of them have the star power or charisma or whatever like Downey, Evans and Hemsworth. It will be difficult to replace them. They are Iron Man, Capt. America and Thor... I'd have trouble watching them in anything else.

I really liked the Fantastic Four as a kid. I would like to see a movie done properly. The Thing needs to be bigger and better. And I hope they do a better job with Dr. Doom if they bring him back. I trust Marvel to do a good job with most anything.

Krasinski would be a really good choice.

Nonetheless, I hope Downey and all of the current characters stick around for another decade. But I get it if they want to play other roles. They certainly don't need the money.