Flowers is a guard, period. There are four seasons of tape of Flowers attempting to play tackle. Here's a sample of how that went.
Regarding Austin Jackson's inconsistent tape last year, don't forget that he donated bone marrow to his sister prior to the season and it can take as long as 6 months for the body to fully recover from that procedure. I think he'll be up to the job physically this season. The learning curve will be steep, though. I can see the coaches going with Davenport early in the season since the rookies won't get an offseason program.
Michael Deiter is a developmental center at this point. Maybe he plugs back in at guard if Flowers goes down, but I hope not.
My dream scenario on the right side would be for Hunt to stick at tackle and Kindley be ready to start at guard next season. But it seems more likely that Hunt becomes a stud at guard, Davis holds down tackle until we find a better solution, and Kindley backs up at both guards.