My take: it begins with customer segments and user personas. One UI/IX will not fit all. Noobies and power users are the two obvious personas. If one wallet is to serve both, then we need modes of operation. More likely, different products and service will serve different customer segments.
Relai, for example, does a great job catering to normies, as does Strike.
Of course, the trick is that in Bitcoin, we have the additional, crucial dimension of custodial vs non-custodial.