Replaced fuel pump. No difference. Still 42psi at idle, climbing to ~55psi under sputtering free rev.
Having played with it more, I have to say the hesitation is the worst whilst going into 1st. Almost impossible to get going when it stumbles.
Update: Moved it out of the way of my driveway a few minutes later and it acted absolutely perfectly well behaved (for the two times I gave it pedal while semi-walking it). Gave it some free revs afterwards and after a few it started stumbling again.
Also, just caught p0458 (Evap) but if I'm not mistaken that's because of my new Perrin fuel rails/lines, correct?