When you mean bottom 15 defenses, are you thinking pass defenses, or total defenses?
Also, another wrinkle to consider are QBs on teams with bad defenses that play bad pass defenses. That would heighten the chances of huge games, no?
14 Team w/FLX .5PPR
The Porkchop Express
QB: Carson Palmer, Vince Young
RB: Maurice Jones-Drew, Matt Forte, Reggie Bush, Tim Hightower
WR: Greg Jennings, Anquan Boldin, Terrell Owens, Jabar Gaffney
TE: John Carlson, Ben Watson
PK: R Gould
TD: NO, TB