A tablespoon is fine. You should see my version of bread and butter - it's a tiny piece of bread torn off a baquette, and a HUGE pat of butter, like an ounce! LOL! :)
You'll find a balance with your oils I'm sure. On your diet you're getting very few "hidden" fats, so you can afford to get out your oils, make your salad dressings, pan-fry in a combo of butter and olive oil, or coconut oil, liberally butter your veggies, and you'll be just fine. :) yum yum!
Triphala will definitely help! but after the flush try to take some kind of fiber. All you really have to do is eat a fiber-rich meal sometime after the flush to ensure that no stones get stuck. If you can flush your colon somehow, whether wtih a dose of Epsom Salts
, or a salt water flush, or a colonic/enema, this will go a long way to ensuring that you don't get really tired post-flush. But the fiber should be enough to ensure that no stones get stuck.