Here's a little counter-intuitive move that might make sense.
First: there is no reason that Woods cannot take the deep routes. He has plenty of speed for that. You don't have to run 4.3 to take the top off the Defense.
Second: Kupp just might get moved to the outside WR; not sure which side. He has the moves and smarts to play any of the WR positions. Besides: it sure feels as though the Rams are going to gear up to run a lot of 12 formations, which of course means only 2 WOs on the field. And that is going to be Woods and Kupp.
Third: There's a couple of ways to skin a cat on the slot WR. On the small side but can change direction quick as a loose chicken . Or, bigger where you can bully a slot CB or make the D use a safety.
So the idea that if the Rams draft a WR that they have to have a super fast guy who plays wide to replace Cooks isn't necessarily so.