I'm still getting back up to speed with Elemental (LH).
I've seen a few threads now about Champions being a little too weak in the later stages of the game, and the skills trees being a little too 'deep/long' for some classes.
Another thing I've noticed is that I'm not picking a lot of the tree paths, because another tree path gives a better benefit for my style of play. This is not necessarily a bad thing, but if a particular tree path isn't being chosen by most players, well it's kind of pointless to have it to begin with.
So, anyways, I'm thinking that the following ideas might help with the 'compression of skills trees' idea, and help with game balance a bit. Any one of these ideas would help.
1) Lower XP requirements for Champions to advance a level - this will increase level gains, which incidentally increases HPs a bit (as you will gain them more quickly), and give you more skill choices. Not my favorite idea, but easiest to implement.
2) Additional XP awards. I've seen it mentioned a few times now that +1 XP a turn would help. This isn't too OTT, but will allow 'parked' Champions to gain levels while administering Cities. I'd also argue for an additional +1 XP/Turn when administering a city, so that Champions stationed in cities gain +2 XP/turn instead of 1, but that's open to discussion of course.
3) Choosing 2 traits every level instead of 1. This allows more of the skill trees to come into play. This would be limited a bit, in that you would still only be allowed to choose 1 trait on any given skill tree (i.e. no '2 deep' picks) on any given level gain, but then more of those other traits will come into play. This increases the overall value of Sovereigns/Champions in the process, especially in the later game.
4) Increase HP gains for level gains. I think this needs to be more generally applied though, i.e. any creature/unit/hero gaining a level gains more HP than they are currently. Specifically for Champions/Heroes, though, so they are more survivable in the later game.
Those are my thoughts. And discuss...