krieger
Banned
Wearing too many crowns at once will likely lead to weakening royal power in all these kingdoms - even worse if the Jagiellons manage to get elected to Czech crown when Vaclav dies.
Not to OTL extent, and not every TL has to be ideal. Despite of existence (or not) of certain royal, people will also have flaws. While the situation I envision, might not be the best deal for Siggie or even Jogaila himself, it can be a fairly good deal for Garai (for example). He has more freedom in his actions ITTL, because he can proclaim the heir of Angevins a new king even without the consent of his father. This way, Garai can become de-facto ruler of Hungary without being hated by a rest of nobility, he can have Polish swords protecting his power and he can block Ladislaus d'Anjou a road to the throne. For him, it'd be the dream. And Jogaila is forced to collaborate with him. And Bohemian crown became elective only after death of Vladislaus Posthumous.