I did some major LAG changes to my game, but i'm wondering if Zoom by itself did not seriously boost VPP/hand. Pre-WC, I got around 0.24 VPP/hand at NL100, post-WC about 0.18. Now I hover steadily around 0.27VPP/hand. Is Zoom just that big a change or is it all my new playstyle?

On april 1st they gave a bunch of players free VPP as a bonus, maybe you didn't account for that?

Probably just variance and a period of getting more good hands at the same time someone else does, creating more big pots than usual.

just keep pushing it in every hand and you will continue to get massive vpps