Which baking dish is best to bake a banana bread?
"Best" is subjective.

The different choices of baking pans will effect texture and baking time. The more surface area the more crust and the faster the baking time.

Recipes call for a bread pan simply because then it looks like bread and is easier to slice. As you noticed, it does require longer to bake.

Muffin pans are also very popular because of the convenient shape and faster baking time.

If you like the shape and texture of your bread in a baking dish then by all means keep using it. I won't criticize you for it.