Hmm maybe Flair? I mean apperantly the whole guest host thing is pretty much making Orton's career hell. Who better than Flair, the man Orton kicked in the skull. I'm sure he'll get a pretty good pop. But I hope they book Flair right 'coz I'm tired of Flair acting like he still matters, when the fact of the matter is this a fresh and new generation focus on it you old fool! (No offense to Flair or Flair fans lol.)
So. Flair doesn't matter, but you want him be GM of Raw. Yeah. OK. That makes perfect sense.
Unless they go the "Dibiase paid us again to have him host another Raw!" route, another legend would be just fine. Flair would do, though I personally don't like the man's wrestling or promos at all. Dusty Rhodes would do, especially if he did a "Cody, what are you doing? Orton attacked me months ago!" promo on Raw. After that, you don't really have anymore that are directly involved with Orton and company.
Of course, you don't have to go with someone that is directly linked with Legacy. Steamboat will do just as fine. Any legend, really. They'll all work.