Let me know if you need more info than this:
UK (England) - Arachnids - Beetle, Dung, You-Piece-of-Shit (oops sorry - that's the wife's nickname for me creeping in)
Personally I think you'd lose something having more Riders. I think there could be more people in the clan in whatever structure you chose to have ... but there is something special with having 4 Riders at the top. And have you thought how hard it might be to source pictures of the 7 Horsemen of the Apocalypse?
To increase numbers what about a sideline stable of the Fearsome Foals or Night Mares
