I just thought I'd update this here with what I have found myself. This is still taking a ton of time, but I've managed to cut this down slightly (ie: no longer going more than 30s).
I'm using litespeed myself, and upped max php processes from 10 to 30. This drove the time way, way down. However, the down side to this is that I'm now seeing 20-30 lsphp processes every time a WHMCS bridge page is loaded. I know it's that specific page, because, well, site's not open yet and I haven't sent any traffic but my own there.
Just thought I'd offer my own 0.02. Seems that they've got an unusual number of php processes spawning here.