Maybe the 52nd or 53 roster spots are questionable; but I doubt it.
The Rams know, barring injury, who they're keeping.
What is more in doubt is a couple of positions that I think they're going to jump on if the right guy is available.
I hope one of them is back up QB. Mannion is no one I would trust to win a game if Goff went down.
I'd like to see the Rams pick up RG3. A think a QB with a different style than the starter is a good way to go unless you can find a really good vet that mimics the starter. Not likely.
I also expect to see them pick up a TE. With Everett hurt, and with Hemmingway looking lost and nearly incapable of catching a football, I think a good reliable, if unspectacular, vet would be helpful.