As has been said Riker is overlooked.. he's easily one of the best officers Starfleet has and only recently got his own ship. He's very smart, quick wits and he rarely plays by the book and likes to improvise (to great success). That makes him a brilliant tactician and given a bit more time will easily fill the shoes of Picard and maybe make his own impression on Starfleet.
Agreed. I would have voted for Riker.
Out of the current list my vote went to Kirk, with Sisko as a close second.