BWG, I actually think we will get away with having Latu almost play both.
I predict, if they keep him at half, he will have double the touches of Luai moving forward as he falls into more of that first receiver role, as opposed to simply left v right.
I think that allows us play three proppy- middles. I think it also allows Luai to play both sides, effectively what Galvin was doing and, it allows Luai to pick his moments better. Quality over quantity and all that.
I might be completely wrong, but I think when Latu played lock with us, he was kind of playing the 1st receiver role, which, while we see a lot of locks replicating these days, he looked to me to be playing more like a traditional seven; a lot of distribution, calling plays, kicking threat, etc.
Your original point about smaller locks being in vogue is on the money I think overall though. The game is going that way and I think it's outstanding. Love seeing little guys changing the game in the middle.
The giant meat-robot wrestling matches of 5-10 years ago grew awfully monotonous towards the end.