See part of me understands because there are some inherent risk to allowing the creative teams to express themselves more, but I think the reward outweighs the risk for the most part. I also think that it's all in how you (the reader) interpret the work. Where you saw Morrison trying to "out meta himself" others like myself saw him taking a concept from the Superman legend and really playing with it as much as he could. The idea of the 5th dimension was finally given more weight and meaning and really elevated it's inhabitants and the concepts around them. No longer are they just guys from a cartoon dimension where things are just stranger, but instead now they on a physically higher state of being. I don't think there was anything in Morrison's run that didn't plant itself deep within established Superman myth and then just flesh it out.
I think if a team what's to come in and poke around Superman legends for patterns, concepts, and loose ends, and they want to expound/repackage/flesh out/revamp/ or anything to that effect then I say go for it. The creators should always have it in their minds that they are there to write and grow Superman but they must also keep in mind that they are there to actually create. As individuals they have the ability to bring their experiences, dreams, imaginations, and taste that are completely unique to them. I think as creators they gotta come at each project with a little bit of the ego. I respect and like Morrison so much because he's not afraid to use these characters to tell you wants on his mind, how he's feeling, what he's into. That's how these characters were made and sustained. It was just kids and young adults just telling the rest of the world what they liked and what they felt. Superman's creators? Loved sci-fi books and mags, bodybuilding, didn't like bullies, and felt alienated due to their heritage. Then in the Sliver Age (where most of his concepts come from) it's been said more than once that it was editor Mort Weisinger's therapy sessions that found their way into the books. If that's not ego then I don't know what is.
Somewhere out there right now there is a kid who wants to make a Superman story where he/she treats it like an indie film or book and it could be amazing, respectful to the character, fun, and a new twist with old and new ideas. We just don't know yet. The road could be bumpy but Superman will come out stronger for it when it's all said and done I feel. I'd personally love to see Landis try his hand at the main book for a few issues (I know he's rather busy) just to see how he'd tackle a Superman that he didn't build up. How would he make the project his own in that situation? Would he focus more on the story to show his personality? The character? Both? But yeah I'm still quite happy (crazy happy actually) to see him try his had in his own sandbox. Could be good--great even or not. I'm just glad to see new voices with more to say on the character than just the safe company standard.