Ruiz would be really nice there at 52. But tbh I'd also be ok with Hennessee, who I hadn't really considered that early until I watched more of his snaps. For me he's that guy at center who I get more and more fond of the more I watch him play.
Starting at center isn't an easy thing as a rookie, but I think Hennessee is smart enough to do it. I also really like his ability to adjust on the fly, he's really good at picking up blitzes and stunts which is something we've lacked since Sully retired. He probably wouldn't be a great value or anything at 52, but IMO he would start day one for us and that would make for a really nice pick.