I agree that for LN non-custodial on mobile like nostr:npub1mutnyacc9uc4t5mmxvpprwsauj5p2qxq95v4a9j0jxl8wnkfvuyque23vg it brings new UX challenges, but with recent work on auto-accept and more research on background services I'm convinced it'll get better.

And non-custodial non-mobile like if you're running your node on umbrel or start9 + NWC backend connected to your node its already pretty sweet one-tap zaps UX.

What do you mean "a centralizing factor"?

I don't think you should limit the flexibility of what a client can offer in terms of wallet interaction.

The same way you present on nostr:npub1mutnyacc9uc4t5mmxvpprwsauj5p2qxq95v4a9j0jxl8wnkfvuyque23vg a list of nostr profiles you zapped, a nostr client should be able to present the list of transactions you sent/received from different profiles, grouped/filtered by several preferences.