Triethenolamine, also often seen as TEA, is an emulsifier, but nothing I would personally use. From what I have read, it can be known to cause allergic reactions, and it has toxicity issues in regard to aquatic life, and it does end up down the drain; (there are also some other studies about it that get kind of ugly.)
DMDM Hydantoin is a preservative that is a formaldehyde releaser, not something I care to use, but I see it in far too many products.
I made an all natural face face scrub three years ago, there is no water included, only carrier oil and it only started to separate after a couple of years, with no adverse odor from the oil being that old. It's a weird one, but I can share it if you'd like, you could at least see what I did. I still use it on my face with wonderful results.
Yes please! It would be interesting to try out various options