It's not so much the crunch part, it's that why are you keeping Treadwell at all if he's not going to see the field? I guess you could draft a project WR late but I wouldn't put much of a need there. Thielen, Diggs, Patterson, Treadwell, Johnson/Wright is a pretty decent group. Anyone you pick up is going to have to slot at the bottom of that group, even if you don't retain Patterson.