Obvious? Hogwarts traditions didn’t begin with Harry Potter. Personally, I see Ravenclaw as a good choice.
But that doesn’t really answer your question. The fact is, Gryffindor is considered not just brave, but noble, as in ‘hero’ material, and being there does not mean you are not intelligent or ambitious, just that your nature is courageous as well as your other traits, e.g. Hermione, who chose Gryffindor.
And furthermore, it is worth remembering that the three characters in whose company we spend the most time are Gryffindors, who would obviously be happiest with the House they were deemed most suitable for. I’m sure the Slytherins and Ravenclaws are equally proud of their House.