McDonalds started out with a simple menu, just like In-N-Out is doing. 5 Guys seems to be a progression of In-N-Out. I actually avoid In-N-Out because of the horrible fries. Haven't tried 5 Guys yet.
Whataburger is a joint started in Corpus Christi Texas. A straight up, no bull****, no gimmick freshly cooked burger and fries or onion rings. Good stuff. Last time I was in Texas, my father drove me straight to WhataBurger for dinner. I hadn't even taken a leak after a long drive. But their bathroom was spotless before I got there.
I still prefer Wendy's fries and Sonic Onion rings, as far as fast food goes.
Otherwise, if you haven't figured out how to cook your own favorite burger by now... My favorite invention is white bread, lightly toasted, 80% hamburger meat, flipped ONLY ONCE AND NOT SQUEEZED, and depending on mood, onion, ketchup, and either mayo or mustard. Side of pickle. Gotta love the pickle. Raw Jalapeno.