I struggle to with this decision also, and have for years. My bangs tend to be closer to a 4a when dry at what would be a natural bang-length, when the rest of my hair is in the 3s, so I have kept them very long or nonexistent because I couldn't figure out how to wear them. I'm always afraid curly bangs will date me as a child of the 80s. I'd love to see what others suggest.
My in put is that you do it, go long -longer than you think you'd want them initially. You can always cut shorter later.
3a/3b hair, baby fine texture, just past shoulders
Currently returning to a CO routine