I would think allainces would be a fun choice to add, I've seen other peiple suggest it but I would like to make me own suggestion.

In general alliances will basically one giant friend group, where you canjoin anybodies match, be able to talk about tips and tricks but one thing I would add is allaince battles/ a attack or defense for an alliance base, it would create teams, chaos and I think it would be a fun addition. For the buildings to attack, it could be built based on how many quests (stuff like: revive 10 people, or have 20 people spawn on you, etc.) or the more people a allaince has the better the buildings., the buildings are more for a show of power and statues than anything else.

There could be different factions of allainces such as Coalition, Ore, and Mercenaries.

Coalition
They are part of the whole coalition team, they can attack Ore and mercenaries while being able to request help from other coalition forces. They wont be able to attack other coalition forces. There could be buffs such as a greater buff in both attach and speed when attacking a alliance due to the fact thet always attack in rush game modes. Their buildings will be more of a natural color scheme, like their camoflauge.

Ore
They are able to attack Coalition and Mercenaries and can request help from other Ore allainces to attack. They won't be able to attack other Ore allainces. They can have a buff during defense since they are defensive during rush as well. Their buildings will use a primary color of black, with some minor color like dark red, dark blue, dark purple, etc.

Mercenaries
They are able to attack anyone including other mercenaries, and they can anyone if they are paided with something, it could be exp to level up their allaince faster. They wont have any buffs when attacking or defending allainces. Their buildings can be nesrly any combinationd of colors as well.

I think this could be a fun addition, but if this is not a way the devs want to go, oh well, but please atleast think about it and read this.