One of the things i feel the most is the separation of nostr and lightning. (Which imo ZBD has solved).
That integration should be the default, with advanced options available. Every client should become by default a lightning custodian.
Every client should use nostr, but build as if they are one stop shop solution. This reaches more people.
At the moment, you either are not a techie, and will be getting half of the experience. Or need someone to walk you through onboarding, or a techie and know what you are doing to enjoy the full experience.