it all depends on what WWE wants out of him. First off he hasn't had any mike time, so theirs no telling for sure but I think they're leaning his character towards a tweener/Face instead of a heel. I mean he hasn't lashed out at the crowd or beat up any fan favorites. If they plan on running with his push and making something of him, then I'd think Mark Henry would be the perfect one to put him over.
To me Mark Henrys the no brainer because he's out of the main event picture, theirs just no room for him and there shouldn't be. I'm glad he got his oppurtinity with the gold be he doesn't need to be back there, The face of the industry should be fresh right now and he debuted back in March 1996, eight months before The Rock and less then a year after HHH. So even though he's out of the main event, he's only recently out, so it would still be a perfect guy to but over Ryback. He beats a guy who was recently the Champ, and wins over the crowd cause people love to boo Henry. And for those who were asking if he was strong enough to go up against guys like Big Show and Henry, I'd say yes, the guys huge, he could probably pull off a cleaner attitude adjustment on Big Show than Cena can. However Henrys got the heat so if they want to give him the best push possible Henry has to put him over.
Damien Sandow could be an interesting one as well, it would be a great way to show case both new comers. It could play out like this, Sandow continues his gimmic where he comes to the ring only to tell the audience that they don't deserve to watch him wrestle and walk out. He does this for a few weeks, until the man standing in front of him is Ryback. As he attempts to leave Ryback throws him back into the ring and forces him to debut. This way the audience gets behind Ryback, for taking out the guys who's been insulting them for weeks, and Sandow gets to show off some of his size and power against Ryback before ultimatley loosing