Have you considered Cashu? - Doesn’t require KYC - Users can select their preferred custodian (removes liability from Primal if custodian is down) - Provides Lightning and ecash capabilities (nutzaps/new features become possible) - You can run your own npubx.cash server for providing Lightning addresses - User’s balance and transactions (outside of public zap/nutzap events) are private Here’s a quick demo to show how easy it could be to implement: