196/174 @ 12psi is not all that bad considering the 2 1/4" exhaust, and the crazy rich up top. I lose power on my car due to 10.8 afr's on the top but you completely flatline at 10:1 afr's. You could gain 15whp up top jut by leaning it out and another 10whp from a 3". That puts you right at 215-220whp right where you should be.
the more i look at your charts the more I wonder why it spools so slowly. It has to be in your 2 1/4 exhaust. When I had the S60 on my 1.6L I had a full 2.5in turbo back w/ no cat. I would see 12psi @ 3700rpm and 18psi @ 4100rpm.