For a very inexpensive but satisfying burger i like a McDouble in a lettuce wrap (so no bun) and hold the ketchup, plus add an extra patty. That third wee patty brings it up to a full 1/3 pound of beef but is much, much cheaper than ordering a Quarter Pounder which is less meat. If you are not as cheap as me then the Angus’s are the really nice burger at McD’s. The Mighty Angus Original in a lettuce wrap “hold the sauce” (sub in mustard or Mayo if you like) has bacon, lettuce, tomato, cheese, and caramelized onions. It’s very good. If you want an egg meal go for one of the breakfast sandwiches. You have a choice of ham, bacon or sausage for your meat and it has cheese. You can add tomato and lettuce wrap (hold the bun). Again, there is nothing stopping you from asking for an extra egg or meat or cheese if you like.
Another option is just go a la cart. Burger patties are cheap, and you have a choice in sizes. The small ones are well under a buck each so you can stack them, but the Quarter Pounder patties aren’t expensive either and I like them a bit better. Once again, you can have the Angus patty, I’ve never done it though and don’t know the price, but it would be even nicer. You can also order Round eggs (basically hard poached), sausage patties and bacon (I assume the ham too, but I’ve never done it). All keto options.
Also, if you like your food as fresh and hot as possible you can always ask for the food straight off you grill. It might take an extra minute or so but it’s nicer. Just tell the cashier to put an “ask me” on it for “right off the grill”.
Not all stores do really nice lettuce wraps. There are two McD’s in my town and one takes a gorgeous huge piece of lettuce and wraps it so it can be held like a sandwich when you eat it, and the other just puts two tiny pieces of lettuce, one on the bottom and one on the top, so ymmv.