One of the big advantages of Alexis playing in the middle, for me, is that you don't have to play Giroud, and you can get Iwobi and Walcott into the team, and have a fluid front four.
Would call Walcott our 3rd best attacking player also, tbh. That said, we could definitely improve our options on the wings, both Walcott and competition for Iwobi. Like @AW49 said Mané would've improved Walcott. I wasn't calling for the signing of Mané so hindsight is 20/20 a bit but going into the season with Mané, Iwobi, Walcott, and Gnabry as our wing options would've been ideal.