I just remembered a pvp system from a game I used to play.
The game is called Global Agenda and it has a pretty nice system for guilds to battle vs other guilds
U have a map with hexes and those area's u could capture, and defend with your guild.
It's obviously a lot more complicated than that, and it would definitely need to be adjusted to work with this game.
But I think it's very possible.
I'm including an image so u can see what I'm talking about.
It should give u a pretty good idea.
If u have any questions about it I can go into the matter a bit deeper.
I've already got some ideas about how to make this work in thesettlersonline
The different colors represent which areas are held by what guild.
These hexes could give a % of bonus resources for the entire guild for example.
And perhaps some rare hexes with bonuses that every guild will want, which would make great competition.
and so and so on
Oh and these maps were open at specific times a day, so guilds could prepare for battle, because a constant battle will be to hard for many guilds to be able to compete.
because u would need to be online nonstop or atleast have members online nonstop, and then the smaller guilds could not compete. but everyone should be able to grab some hexes for bonuses.