Clooney wants to make an A-Team movie and play Hannibal too. He's said in interviews that his three dream roles are to be Hannibal Smith, Thomas Magnum and Danny Ocean. Currently, they're working on an Ocean's 11 sequel, Ocean's 12 with Catherine Zeta Jones joining the cast.
I think Tom Selleck would be good as the voice of Robin Masters. For Higgins you just need someone you can milquetoast and uptight to a T. David Hyde Pierce would be good actually or William Daniels if he's not considered too old. If they want to go the comedic route with Higgians, hire Eddie Izzard.