I've never been happy with my sound, but when gigs have gone well with people really enjoying the band, then I tend to not be so bothered and enjoy the moment, and think I must be doing something right. Everyone else's sound always seems to be better than mine, whatever setup I'm using. Just like every other bass player is better than me (although they are). GAS is built on this. Odds are, your gear and playing is fab, but sometimes a venue will sound poor for bass (standing frequency etc.).
Keep everything; buy new gear; try to enjoy.
And remember; it could be worse - you could be a singist.