One that hasn't been listed.
Relics. Can you make empowerment costs of a relic to reflect the size of a guild, in the same way that mercs are hired?
Smaller guilds who can't defend relics so easily would then at least consider empowering a relic
yes, plus a maintenance fee for empowerments, say if a guild has a relic for 5 days empowerment is lost and relic has to be re empowered. some high profile guilds with plenty of money are getting free rides with their relics.

