I see having a president as no different to having a prime minister, so yes. The devolved nations already acceot an English prime minister and would presumably retain their own first ministers so what would the difference be? As for religion, you know the PM already cant be Catholic? Tony Blair converted only after leaving office. So again, no difference.

The royals may well be a unifying factor for sone people, but NOT everyone. And I support Scottish independence anyway 🤷