AstroZombie
Arcane
Treads on PA are underrated, everyone goes phase automatically but there are benefits to going treads; PA is very weak early on to magic burst and having treads definitely helps with that. It's a common misconception to think that the attack speed is wasted because of the AS buff she gets after blinking - although the recent movespeed nerf on treads made it considerably worse imo. Doesn't affect her as much as other heroes.
The crit works off of PRD, so until you hit the AS cap fully buffed there really isn't any reason to be shy about getting things like treads, maelstrom, etc. given how powerful they are.
You should never be shy about getting a maelstrom on most heroes since Mjollnir is absurdly good.