Actually, there IS: That's what the "groups" in the symbol creation are for. You can turn on and off certain sections when inserting the symbol. for instance, my weld symbol comes in plain, and you add the group for left side tail, right side tail, butt weld symbol, bevel weld symbol, farside nearside etc.
It's a little wonky, and for REALLY complex symbols they geometry on top of one another can be a bit confusing, but it DOES work.
As far as making groups, it does not have to be strictly text, it can be text and/or geometry, and can be quite involved. Take a look at the attached symbol.