If JP's game against Houston proves to be his breakout game, I think you put the priority on upgrading positions this way:
1.) DL - No one is safe except for Schobel. Huge numbers on the ground have been given up and they haven't looked pretty.
2.) OL - RG is one of the biggest holes on the team. I'd like to see both guard positions upgraded. I think Peters and Pennington both are playing pretty decently.
3.) TE - JP showed that with some time, he can do a good job of checking down on his reads and throwing the ball. I'd love to give him a nice, big receiving threat over the middle - A-train isn't cutting it.
4.) WR - A #2 WR would be great, someone who is a big, tall guy who JP can feel comfortable throwing the ball up for a jump-ball with.
5.) FB - We need a FB who isn't almost worthless. A big time run blocker, Sam Gash type, would really help out the O-line.
6.) Depth. A young QB, perhaps drafted in a lower-round, would be a nice backup for JP. A replacement for Spikes is needed. A backup plan at safety would be nice too.