My band has essentially zero ego issues. I suppose we have defacto leader, but she is cool about other people's ideas, and she is the pseudo-leader because she is by far the most experienced in band activities and playing out live. Almost everyone in the band is a vocalist and songwriter (percussion guy just plays percussion, doesn't actively write), so we bring our own material and we have (usually spontaneous) group songwriting sessions.
But we are all a bit long in the tooth, and we're not doing it for the money, or the glory - mostly we want to enjoy our own music and hope the audience likes it too.
And we are varied in our material: We normally do what we call Celtic Fusion (which in and of itself is wide ranging), but I just finalized the order for our next CD, which is a Christmas CD - a mix of classic carols and songs (all pubic domain!) and a few originals, done in a variety of styles (e.g. Adeste Fidelis starts out in Latin, a capella, and finishes a la Trans-Siberian Orchestra with distorted guitars). We had fun doing the project, we know it isn't going to sell to very many folks, it is mostly a Christmas gift to friends and fans.
Definitely a low-key bunch of folks in my band.