IMO, he's the best tackle going into spring. If other tackles emerge, I'm fine moving him. But I suspect he will probably be further ahead than Kennedy and Campbell based on the way he was playing to finish the season.
I think so. Gaynor is more physical than Gauthier, Reed is much stronger than Mahoney/Boulware and Donaldson should be improved with a full year at guard.
Scaife is lean and athletic, too.
It would be a huge mistake to move Scaife inside, IMO. He is already a good tackle and is only getting better. I don't see the depth at tackle to merit that kind of move.