since your fuel pressure is dead on according to you and you have an aftermarket FPR, i'm gonna say replace your TPS and redo your maf wires, make sure you keep the guage of the wire consistent. If that doesn't provide the results you want then its in your tune. but if you say its running a 10:1 AFR at idle thats a shit ton of fuel thats gonna need to be pulled on the tune.

my car was doing that a while ago and it turned out to be my fuel pressure regulator.