I need some serious advice.....about bean dip?

HELLO. one time someone made bean dip and he said all that he put in it was velveeta, refried beans, and a can of tomatoes and green chile. you know how you can buy those cans where they’re already combined? yeah that. well, the bean dip was out of this world, but the thought of using velveeta is not one that i enjoy, so what do you think i could replace the velveeta with that would still taste as good? i have mozzarella and monterey jack but i have to go to the store anyhow. also, how could i make my own refried beans that are comparable to canned ones? i dislike canned ones because last time i used them i got very sick and it was the only factor that was different than usual.

SO:

what cheese(s) can i use in place of velveeta?
and
what do i need to put into my refried beans? whats a good bean to cheese ratio? last time i made burritos i put too much cheese and it was way too stringy. thats why im seeking guidance here.

gracias!