I think you may well be right. Plus, even though we've seen Buchanan make his mark at a high level, he may get a good deal of game time this season. As a young bolter I'll say Jack Clifford, although the back row is so competitive that's a bit of a punt. He looks very classy though.
They were Luke Wallace's tips last night, too, so you may be onto something. And Stuart Lancaster has effectively tipped Matthews by mrntioning him as one of the players who just missed out on a Saxons spot.