Think he is more of a false 9 than a number 10 imo, think our midfield would get overrun if we played him behind Auba...but our midfield gets overrun in every game these days no matter how many we have in it so why not try it!
You'd probably have to play a double pivot of Torreira/Willock behind him to stabilize things. But then the question is again who gets the ball forward centrally. Would be a very wing focused approach with Laca as more of a decoy, wallplayer and hard working 10/9.5 but who at least would be an attacker up there instead of a DM.