I like the gender-role reversal of cartoon stereotypes in the show. The wife is the crazy idiot, the father is the level-headed ruiner of fun, the horny teenager is a girl, the mischievous brat is a girl... too many cartoons copy The Simpsons gender role formula and I like how Bob's Burgers more or less reverses it. It's refreshing to me.
I also like how Tina looks/sounds very nerdy and plain but does well with boys. Instead of changing the horny loser-in-love from a boy to a girl, they changed the gender and made her not a loser. She seems to not fit in with the other girls though. Other than her sister, I only recall her being friends with Tammy but that didn't last long.