That's a pretty decent ensemble.
I like the logic here. Surround your lead with a strong supporting cast, that way the entire film doesn't rest all on the newbie.
To appease the rabid fanboys on costumes, what I'd do is follow Random's idea for story. Opening to the film would be a battle similar to the opening in Gladiator. In the battle, I'd have Thor in the classic 616 costume. He'd win, then we'd watch him celebrate in a most immature manner.
Then he'd be banished to Earth to learn humility. Blah blah blah....Asgard is overthrown by Loki. Odin bequeaths his power to Thor to help him return.
Upon rediscovering his lineage and who he is, when he transforms back into Thor, he'd have the current costume. And then....to please the Ultimate Thor fanboys...in the final battle, Mjöllnir would be cracked or damaged...Thor is then bestowed his Ultimate hammer/axe as a ultimate weapon of sorts. Or maybe even have that as Odin's hammer....which is then passed onto Thor.