The Rams FIRST need to fill gaping holes. It's a luxury to worry about 2 or 3 years down the line.
The Rams have serious holes at Edge and in the Secondary. We also only have 1 good ILB.
But, the Rams have excellent WRs.
I think your evaluation of Kupp isn't quite right. He is fighting through injuries this year. An off season will bring him back.
Then we have Nacua who is about as good as it gets as a WR.
All other WRs need to be complimentary to those 2. We have those right now, not that perhaps we can't even do better...but not as a priority.
The beauty of what we have now is that the only expensive WR we have is Kupp. Nacua is a getting a 5th rounders salary....cheap as it gets. This allows us to spend money on positions of need. And, that is what the Rams are going to do.