If you can improve your team you do it.  Saying that our WR group is already loaded and we need to work on our perceived weakest group is I suppose one way to go.  But if you can make a group really elite, you can beat teams with it. 
I remember when we signed AD.  People complained because our D-line was a strength (maybe our only one).  That defense probably was the only reason we won the games we did. 
Bringing in someone's cast off O-lineman is not going to help this team.  Bringing in a truly elite weapon that can get open before the rush gets there and make defenses pay, will.