Baked beans have other flavors in them, but yeah, there’s nothing stopping you from having baked beans on a taco. If you’re anal you could rinse them off I guess.
Looking at supermarket websites for your area of the planet your bean selection kinda stinks. I didn’t realize how many are available in the USA.
Healthiest bean is Lentil overall; never tried lentils for burritos but there’s no reason it couldn’t work. Kidney of course, although you might feel like you’re eating Chili… then again you got baked there.
Most of the difference is psychological anyway. Fundamentally, a burrito is the same as British “Beans on Toast”. Beans is beans. Bread is bread.
If I wanted a taco and all i had was white bread, I’d flatten the hell out of a few pieces of bread, stick them in a frying pan with oil/butter/whatever and toast them super-flat. I’d add salt to both sides ’cause tacos have salt.
Then, make a sandwich. It’d be wheat-based instead of corn-based but it’ll work. If you’re clever, you could probably shape them somehow while you’re toasting in the pan – maybe a square “U” shape. Might also make a mess but so what tongue emoticon