Stripe’s tax features have worked well for our use cases so far, and we also have experience with Avalara from previous projects. Would you be open to connecting over a video call to discuss your specific needs? I think it might be easier that way as it's a broad topic :)
I don't have a need at the moment just curious. It looks like Stripe Tax doesn't support all US states. Will probably be a good product when it's out of beta!