Also instead of burritos think about burrito bowls like at Chipotle. Basically rice, beans, grilled or sauteed peppers and onions then salsa, corn salsa and little bit of avocado if you can. You can also make lentil or white/cannolini bean stews. Celery, onions, garlic, carrots etc in a pot, add some salt, pepper and whatever herbs you want, low sodium veg or chicken broth. Throw in diced potatoes and kale or spinach, cabbage if you prefer, maybe a can of tomato and add a can of white beans or some lentils. Very cheap, low fat and you can season it up however you want, lots of fiber. You can do a Mexican version with black beans and sweet potatoes. Make a big batch and freeze half.

People make chickpea "tuna" salad which is just mashed canned chickpeas dressed like a tuna salad. When I was avoiding all fats I added Dijon mustard and a little avocado with celery and onion etc. Here's a recipe I found: https://spartanlifeblog.com/low-fat-chickpea-salad-sandwich/

A lentil recipe: https://spartanlifeblog.com/10-minute-savory-lentils/

I just found this blog but you should browse the recipes, I bet there are a lot of ideas for you.