[WPMU DEV Dashboard] My site is too big (37gb) I would like to know what plugin to use to make it

I've been running Smush for the last 3 days and that's save 3gb already and it's only at 45% but I know that it's still gonna be way too big even after it's finished. I want to move the site to WPMUDEV for hosting but I'm trying to srhink it first. Any ideas?