I don't think PR/KR have much value. Frankly, I've always thought that teams could either Fair Catch or let the ball go, and down it on kickoffs, and be right about the league average for returns anyway. It's great when you have one of Those Guys, but those guys are rare. You certainly don't trade for one. The value isn't there.
A fifth WR never sees the field in the playoffs. The Rams's scheme itself devalues the ILB spot, and Jones looks promising there, anyway.
Corner help would be good, but the best way to help the corners is to put pressure on the QB.
The Rams have Donald up the middle, and Lloyd from the edge. Offenses can put a TE on Lloyd's side, or the RB. With Miller coming from the other side, the Rams will be placing pressure up the middle, and from both edges. So now, the offense is either going to run double TE sets (and make the secondary's job easier), or take their chances on man blocking. Over the course of a game, this is an advantage to the Rams. Furthermore, it helps contain the rash of mobile QBs that have sprouted up all over the place. More pressure on the QB, and better contain on QB scrambles...that's what this trade should do.
