In Big Fish, we have a council of 6 players currently, but decisions can be made with a majority 4 vote, and 2 of the members are mostly silent (unless an important decision needs to be made. Our tribe is split up into squads, which are organised into groups we call battalions. All the council members are either leaders or 2IC's of battalions, and we use the council mainly to seek advice brainstorm new ideas, and make important decisions that affect the whole tribe. Other than that, each battalion general has autonomy over their own battalion. They may ask advice of the council, but they don't have to.
Most of us were promoted through being good squad leaders, to battalion generals when the old generals left the game or were promoted themselves. Our man who holds the founders badge was immediately given a council seat after a merge, however that does not usually happen now as any tribes merging are a lot smaller - instead the leaders are made into squad leaders.
Anyone can be considered for a council position if one becomes available (more than 6 is too many imo - we recently added a new 2IC, before that there was 5), but they need to have shown initiative within the tribe, to look out for their tribe-mates. For example, I was running a squad when my battalion general became very ill and wound up being hospitalised before he could notify us of inactivity. I noticed he wasn't around and that the battalion was suffering for it, so I stepped up in the interim and reorganised some things, got people talking again, and working together again. When he came back, he made me his 2IC and I was then promoted to general when he was given the founders badge.
Council members are expected to be active in the forums and mails, and to encourage activity and communication within their battalions. They can also assign targets if the squad leaders are not picking any, and they can help coordinate inter-squad attacks, and extra support. They keep the squad leaders accountable and encouraged, and also give advice to anyone who requests it - they are expected to know the game well enough to teach how to play if need be, and also to advise on leadership if the squad leaders want/need it. They also need to have a certain level of maturity, in order to be able to deal with dramas that may arise professionally.
It's all basically a delegation - having 100+ players in a tribe is a lot for one person to keep up with (at one point we had nearly 200), so the squad leaders look after 5-10 players, then the battalion general looks after 5-10 squad leaders, and report to each other for advice and encouragement etc.
It can be fun within the council itself, with differing opinions and personalities, but we have learned to work together in spite of differences, and for the most part things are good - we don't do anything rash, especially if someone is upset, and we know we can privately vent to at least one person in there if need be. It works for us, anyway
