I think technically, he suits being a number 10 more than anywhere else. He has very quick feet and a lovely touch and weighted pass. He is also calm on the ball. However, he is not so calm off it, which leads to poor tackles, which in CM causes big problems. I think Davies would be especially good against the lower teams with 10 men behind the ball, where he can find space, turn the player and play a through ball.
Where Davies needs to improve is through his finishing, and getting into the box, and this is why he will be behind Siggy in the pecking order for the timebeing.