Not that you can't put anything at all that you like on or with felafel but like KKA, I like to keep it a bit authentic

and I like to diy. I

raita but prefer it with South Asian food
Felafel on salad inside pita is a fantastic fave street food - at home we usually serve deconstructed, plated, with the sauces, salads, pita, and very importantly, mideast salt fermented pickles. Hummus is usually a separate dish.
Fave sauces:
garlicky lemony unctuous tahini sauce
zhug, especially the green, but also the red
fermented harissa sauce