Yeah, double-posting's a no-no on LAF.
It took me a while to figure out where people were talking about SB myself - like you said it could live on several different boards about equally well. Doubt it'll get a child board somewhere unless it really takes off, but maybe there's room for something like a "Fantasy Historicals" board that could cover SB, Flintloque/Slaughterloo, Panzerfauste, etc. Trick's getting enough traffic volume to really need it.