I use a PS5 controller and it worked great right out of the box. It also has the added bonus that you can use the touchpad on it as a trackpad to control your mouse cursor.

Agree that the cheese should be the star of the show. In my mind a grilled cheese is basically just an excuse to eat bread and cheese. One ingredient I like to add is a sprinkle of garlic powder between the bread and the cheese (not on the outside, it'll burn very easily in the pan). Just enough to add a hint of garlic flavor.