Romania has the best system for 2021 as it actually closes the undeniable
democratic gap: they have an elected president. At the same time, within the republican framework, the former Royal House is recognized and has a ceremonial and protocollary role in society.
This symbiosis of a Royal House inside a republic is no
nouveauté: the United Provinces of the Netherlands (1588–1795) were formally a republic but they effectively had a Royal House functioning within the republican framework (the House of Orange-Nassau).
Picture: Princess Margareta adresses the Romanian Parliament. On the screen, in the republican Parliament:
"H.M. Margareta, Custodian of the Romanian Crown". Note that the lecture still has the un-adapted republican Arms (
uncrowned eagle as shield bearer) while the wall of the Chamber now depicts the newly adapted "royal" Arms (
crowned eagle as shield bearer).
I would not mind my country (the Netherlands) becoming a republic, with a ceremonial and protocollary role for the former Royal House. In essence most monarchies in Europe are already ceremonial and protocollary anyway. It would take the angle out of the debate as
hereditary succession simply is hard to defend anno 2021.