I realize it may not be the popular or sexy concept--but consider the impact of drafting Pettigrew at #21. A huge BLOCKING type TE. The key to offense success is balance. If the D has to prepare to defend run and pass they cannot optimally stop either.
The potential impact of another massive drive blocker makes any snap a 4-5 yard average run, and sets up play action. In terms of keeping a defense honest, this forces other teams safeties up into the box letting Curtis/Jackson etc.. burn by them.
IMHO--this may have more potential offensive firepower then necessarilly adding the "#1 receiver".