Since my suggestion immediately got bumped away, reposting.
In terms of ideas, there are quite a few things you could do.
One of the things Ol'West really lacks, are reasons for alliances.
One idea you could do is, have crypt alliances, where pairs of guilds could team up to capture the haunted house, which, could be similar to bases.
Instead of explicit capturing, whenever the guild flag reaches zero, a door to the crypt could open, where, inside, a crypt-like instance waits. If another guild raids, they can go in, and, take the instance, if, everyone inside dies, the crypt resets.
So, for example, if, Greed captured the base, one strategy would be to have a fourth of the members crypting, and, earning points for the guild, while, the rest of the members defend the entrance.
You could also use this as an opportunity to get the first guild symbols out, perhaps as well as tokens for the guild, guild tokens are also rewarded per wave, which, could be used to purchase symbols, as well as temporary reputation, and, gralat bonuses for skilling, to promote basers skilling, and skillers basing.
Haunted houses could spawn randomly around the map, in which case, guilds would have to scramble to gain control, and, finish the crypt as fast as possible.