I'm not sure who I'd want as the new Captain, but I would really love to see Ron Pearlman (Beauty & the Beast/Hellboy) as the Chief Engineer.
Maybe Joe Flanigan from SG-A would be an interesting choice as the Captain.
I'd like to see Flanigan back on TV, but I really don't see him as the Starfleet captain type. He's the kind of actor who should stick to the type that suits him. He could be a Han Solo-ish space rogue, for instance, or even a Boomer who joins Starfleet and clashes a bit with the restrictions (Mayweather the way they should have written him).
Pearlman would make a good colorful character - Cardassian or Orion badass. I wouldn't waste him on Starfleet.