I've read a lot of threads about this problem (only hitting wastegate boost), about how it's due to the missing restriction pill and/or bad BCS (I found both for very cheap, and will get the parts soon). In the meantime, I did an ECU reset and cleaned out the BCS with MAF cleaner. No change--and I did feel around for the pill but the vacuum line is so stiff it's hard to tell.
Anyways, is there any recommendation on anything else I should be on the lookout for? I've posted a datalog below, it's hard for me to redline to 3rd because of the area I live in, but I don't know if it's even worth it since the problem is pretty apparent. It's a stock, Stage 1 (ACN 91 v310) WRX (with SPT intake). Thanks guys.