Favorite/highest quality sandwich ingredients?

I pack a lunch to work every day. It's tasty and saves money. As I don't have the energy to find something unique, I usually end up taking a sandwich. Looking for ways to elevate my game and/or save money. The sandwich I usually have is a pretty basic ham & cheese, but discussion of all types encouraged!

Bread: I am fond of sub bread over white, and fresh is superior. The bakery sub rolls from walmart are my current winners. I've considered buying a fancy breadmaker - it's cheaper (eventually) and it doesn't get fresher. But I'm not sure if fresh white bread would be better than sub bread.

Ham: I've taken to buying the whole hams that you cook yourself. They're way cheaper per pound than deli ham and great quality. Plus you can flavor to taste. I typically use a pretty basic brown sugar glaze. Cook about one a month depending on size, portion into week sized bags, and freeze.

Cheese: Due to being lactose intolerant, I find myself limited in exploring the wonderful world of cheese. I use cabot brand, which is made nearly lactose free by their process. I enjoy the white and yellow cheddar.

Sauce: I enjoy sauces with a mayo base, but don't love mayo on its own. My current sauce of choice is boar's head honey mustard from Publix. Every other honey mustard I've tried is either too sweet or too mustard-y. I suspect this is because they aren't formulated for sandwiches. I bet I'd love the honey mustard from other delis like subway. And I'd love to find some new sauces that I can make myself and adjust the flavor to my liking!

Extras: Personally, I've never liked many toppings - tomatoes, pickles, olives, raw onion, peppers, etc. Lettuce and spinach offer a nice crunch and some refreshment.