You want powerful late night quesadillas, you need TexMex
Our bastardized Texas versions of Mexican food include lots of quesadillas.
Mozzarella is the wrong cheese. Cheddar and Monterrey Jack, please.
MEAT, MEAT, MEAT. Chicken, steak, grilled shrimp, crawdads, roasted pork, chorizo, anything will do. For the vegetarians (as we say, a Native American word for Bad Hunter), use good mushrooms maybe. Add some kind of mild-to-moderately spicy peppers like poblanos or just green chiles.
Use flour tortillas instead of those silly little corn ones.
And as others have mentioned, serve with sides of sour cream, pico de gallo/salsa, and guacamole.
The one thing your crew got right was slicing it like a pizza. That gives you points to use when dipping into the sides, which should obviously be served in little plastic containers that are otherwise too small to dip large things into.
But that kapsalon stuff sounds worth a try. You kids do some crazy things with chips.