I'd go after two receivers in this class, one early, one late. Luther Burden III would solve so many issues; he's as physical as Kupp and Nacua, while providing burner speed. Only reason I could see him fall to us is because of his nagging injuries this year (and extreme quarterback ineffectiveness this year as well), but I'd pounce on him, given the chance. I love Whittington, but LB3 would be the X receiver we need (and I still think Whittington - and Davis Allen, for that matter; as far as I'm concerned, he's won the job over Parkinson and Long) has untapped potential).
And I know this is going to sound so unpopular, but...Kupp. The elephant in the room. One of the few tradeable assets we have. As much as we'd all wish he could stay, the Rams cannot afford to pay him as much as he's making to be ineffective - and I guarantee that Nacua, Turner, Avila, and possibly Young (depending on how they view his age) and possibly Evans (depending on if they're willing to keep the punter) are going to get extensions soon. Nacua getting a well-earned extension is the key reason I'm trading Kupp for a second, if I'm McSnead.
They cannot move Stafford. This quarterback class is a walking disaster that just gets worse and worse. So, give him protection on the line - preferably a swing tackle/future left/right tackle - receivers and a tight end who can stretch the field (maybe that's a third-round pick? Or first; I think Tyler Warren's shot up into first round consideration after the year he's had, and McVay might look at him.), and keep a solid backfield of K-Will, Corum, and Schrader.
It's not going to be easy, and there's going to be bumps in the road...but I have faith in this team, as always, and I never feel it'll be misplaced with the coach and GM we have.