Is there any way to make a dynamic trait, like the dyanmic mutation system?
Break each trait down into 3 ranks (for example Charismatic might be Rank 1 - +1 happy for monument and other building, Rank 2 - +1 happy per city, Rank 3 - -25% XP requirement) then after maybe 150 turns (or whatevers appropriate) the emergent leader gets offered a trait with 4 ranks based on what he's done. For example if he's founded 2 religions, fought a big war and built a few cities he might get offered a trait with 2 ranks of spiritual, 1 rank aggressive and 1 rank expansive. Or make it multiple choice and offer him either that, Spiritual as it is now or one which is rank 1 spirit, rank 2 aggressive and rank 1 expansive.
Also offer the option to decline those choices and then after another 150 turns they get another 3 traits generated but this time each has a 50% chance of having 5 ranks. If they leave it for another 150 turns then all will have 5 ranks.
Another option if breaking down traits into ranks might be to have each emergent leader start with no traits or a rank 1 or 2 trait and then gain them all throughout the game. Each leader would be able to earn a max of 12 points worth of traits where upgrading to a Rank 1 would be 1 point, rank 2 +2 points and rank 3 +3 points, so a standard leader with 2 traits as they are now has 12 points worth.
Have a system like the great person point where as you go through the game you build up points till you fill up and can then buy a trait or upgrade an existing one. Reward certain actions for example if a leader with spiritual 1 founds a new religion then at the next upgrade the upgrade to spiritual 2 might only cost 1 point instead of 2.
All the unique traits the emergent leaders have now could be little 1 point 1 rank only traits, or maybe expanded into a full 3 ranks (or maybe even expand the traits as they are now into 4 ranks, for example aggressive 4 might give combat 2 for free or something). Negative traits could be taken, for example you could take Agnostic which would do as it does now, block access to spiritual but give you an extra point or 2 to spend on your traits.
And I'm going to stop there because I just realised that as I know nothing at all about modding all this could be totally impossible to actually do. Though would something like either of these be a half decent idea for emergent leaders?