I didn't list a #4 WR because on most teams the #4 WR is a special teamer who can be on the field 5-15 snaps a game which Edelman can handle.
Seriously, why is all the sudden the #4 WR becomes such a big concern. We went into the season last year with no back up for Gronk or Hernandez and no legitimate starting safety opposite Chung. At WR, they only had one legitimate full time starter at WR and no legitimate guy off the bench as a #3 WR. Those were real concerns and the Pats overcame them. Worrying about the #4 WR is nothing compared to that or the fact that if Vollmer or Solder goes down that Cannon becomes the teams' starting RT.
As for the TE/WR thing, it is no different than what described. The Pats use Hernandez as WR a lot just like San Deigo used to consider Gates as a WR in a TE's body (still do, but he isn't as effective) or KC did with Gonzo (and then Atlanta). Yes, Gronk is used as a pure TE, but Hernandez is a hybrid and likely to be used more this year as a WR.