It can't be underestimated how important another right back is for us this season.
It's our main attacking outlet on a flank in which we would otherwise have no width. Mkhitaryan, Mata and Lingard (when they play there) all drift inwards, leaving Valencia a lot of work to do going forward.
But Valencia is 32 and clearly required a fair bit of rotating last season. He needs the quality cover and competition in the form of an attacking right back. Left back is fine when Shaw returns, and Darmian can hold the fort until that happens. But if we lose Valencia on the right then we're up shit creek.
If not Aurier then someone else, but it needs to happen.