That's indeed far better; specifically, Firefox ESR with all the calling-home features disabled in about:config and noscript with no whitelist on top of it.
Ideally you'd make sure the one responsible for going through tor isn't Firefox, too; IE at the very least a wrapper such as tsocks when running it or even better, a VM containing the browser and the entire VM connecting only through tor.
Ideally you'd make sure the one responsible for going through tor isn't Firefox, too; IE at the very least a wrapper such as tsocks when running it or even better, a VM containing the browser and the entire VM connecting only through tor.