I often see threads in 'talk' which belong to 'speedrunning' and vice versa. Also with other forums. For the sake of clarity, wouldn't it be better if moderators would move such threads in the forum they belong to?

Most forums do this and it would just help making the site more clear and ordered.

Also, another suggestion: Why not separate the request threads and 'the site' threads with a request forum? All these sticky threads on top of the site forum could just form an own forum.

First thing the current mods probably dont have time for it, checking each thread where it should belong (they probably need forum mods for that if they even what that).

other stuff higher-ups need to talk about

I'm not saying they have to specifically search for such threads. Just if they happen to see one, move it to the right forum.