Thank you for the replies everyone. :)
@Drakestail, that is a good idea, to offer to make custom pieces. I have done that for my friend, but I will try to mention that to customers at shows. It will also give me something to talk about with the customers since I struggle with that part.
@Terah, I love what you said about a theme and having a cohesive collection. Like Drakestail said, it's best to make what you're inspired to make and I was seeing matching pieces as non-inspiring (besides not liking the matchy matchy look, but I've been thinking about it and I'm starting to see it as more of a challenge. I have pieces where I don't have more of the main focal parts, so it could be challenging and fun to make pieces that go despite not having the exact same supplies. That goes with what weekendjewelry1 and Julie said about having something to show to go with another piece, but also have pieces that can be sold seperately. And I could possibly build a collection from there. :)