lol, this gets discussed nearly every year. you aren't the first. Check the /q for full threads on this topic. last year it was the RP threads, the year before it was the mpreg.
I can't remember exactly, but I'm pretty sure Couchy said something like "the board itself is too small to start breaking it up further."
"Necessary"… uh huh…
Boi, the site works fine without these changes.
As Anon above said, it's not worth separating the chan into pieces because it's already kinda small.
You have the ability to filter the content you don't like.