Garlic salt. Cinnamon and sugar, maybe with a handful of Craisins and some cashew bits.
Or, and this is my own personal favorite, use infused oil for popping. Rosemary oil is amazing for popcorn.
I love popcorn, but hate adding a bunch of stuff to it to add calories. I’ve found that Wishbone Salad Spritzersare good for adding flavor and a bit of moisture (but not sogginess unless you add too much) to help the seasoning stick better.
My favorite is their Caesar spray with some garlic salt.