JMS is too focused on the "grit" and keeping it "real"; that's the last thing Superman needs in my opinion. Superman should be a story about wonder and optimism; something to aspire to. I don't want to see the big S dragged down to our level.
I don't know that I agree with that. His Thor was pretty heavy on very epic/classical stuff.
I didn't read but just the first half dozen issues or so. The parts I read were focused on inserting Norse mythology into the "real world" at the cost of Thor's grand Marvel mythology; he even dumped Asgard in the midwest so that we could get the added story of slack jawed hicks pointing their finger at it. It's the kind of disconnect I expect from JMS; after all, this is the man who was handed Spider-man and said, "Great opportunity for a serious book about sorcery and the occult!"
Rising Stars was pretty good; I won't deny that. But I believe the comics strategy for JMS after that has seen him trying too hard in my opinion. By that, I mean that he's overdone trying to be different; overshot the mark instead of keeping his eye on what he has. That's why I think he may be better off keeping to his own creations; I believe he can no longer wrap his head around playing in universes other people built. In fact, I think that having a property with an established history is seen as a challenge to him; he walks in thinking he has to make it different from everything the character is or else he's failed his job.
So I think he'll write Superman...and it won't be Superman. That's just not something I'm looking for; if I'm buying something with "Superman" on the cover, I'm expecting something with things I'll recognize. If I didn't want that, I would be buying something with an original title I had never seen before. That is where Geoff Johns "gets it" and JMS doesn't; Johns gave us everything we would expect from a Superman story and made it fresh and exciting while doing it.