I used to thread my eyebrows, honestly, the hair barely grew back.
I assure you that if you do this it will not grow back thicker. Perhaps it may look darker. But Hair growth is an inside process. So surly not thicker. Plus, like I said, it seems to make the hair grow back thinner.
Hormone therapy is sort of risky, especially if you plan to try to conceive one day. The side effects simply outweigh the benefits imo. Another way to remove alot of the hair is simply shaving. Like I said, it wont grow back thicker. Ive been shaving my face for years. Mainly to get the dead skin off before I apply makeup.