I have a small suggestion for factions, which would be to add a cooldown on the spawn command or add a "CombatTag" so that it is not possible to escape PvP by typing /spawn and being teleported instantly.
I would like to see regular factions (you call it OP factions, it seems. That actually explains a lot to me.) here. Silk spawners, expensive but buyable spawners, creeper eggs, exp bottles, god apples all in the shop.
EDIT: I have a suggestion. Why not be a bit stricter on your rules. The chat is just horrendous, you should enforce the rules more as maybe sometimes there could be little children. I know this isn't a child oriented server, but at least attempt to keep it mature and not just a wild free-for-all.