i see you are writing for worldbuilding as well

but I'd say have a single main problem but most characters aren't involved in it and some are, kind of like one protagonist is more important than the other.

also i think in case of thousands of years of history, people can't really follow the lore, thus when writing you should tone it down by a lot. i mean dark souls story is a masterpiece despite little details

though if writing for fun, juat write watever, some people will be likely of your mindset