Hey, I recommend sticking to bs-css (https://github.com/reasonml-labs/bs-css). Not because I don't think styled-ppx is super cool or amazing, but because it's so cutting edge your 99% chance going to run into an edge case that isn't well accounted for yet (I had a number of issues when I tried it). bs-css is battle tested today, so if you're goal is stability, I recommend it first.
Also you can use tornado.cash for example over Tor. Or any dapp via something like metamask (or another wallet) over Tor.