Here is my problem with the current system of gear, basic stats, and experience; there are 3 systems within the game currently if you look close enough.
1 Monsters
They use only base stats and some random weapons occasionally therefore they never needed anything to keep them in check and this worked for them.
2 NPC Monsters / Trained Units
This is where it gets tricky because there is the ability to make you own custom unit design but the custom unit designer does not update on the fly for equipment prereqs (other than techs) so you can't have it use them. The problem comes from the reduction of limiting factors for gear for these troops. With no encumbrance system the only limitation is training time and money/materials which can be overcome through advanced buildings/techs. Basically we need the encumbrance system for this limitation as well as specific limitations for heavier armors whether it be a initiative penalty, a dodge penalty, it is just darned heavy, or a combination of all of the above would make the point of wearing heavier armor more a decision rather than automatic.
3 Sovereign / Champions
Much of what needs to be said here has already been said in 2 but let me cover the extras here. With the introduction of armor prereqs and the elimination of encumbrance the different paths have become homogenized through gear except for the ability to equip the best armors. Suddenly Procipinee can wield that stone mace which is ridiculous. This final system of perks as many have noted is great and a pain at the same time. You are trying to balance between pleasing those that want it all right now and those that like rewards for hard work at the end but want to get to the end. This combined with the equipment problems already noted makes the game less fun. I have been experimenting with xp changes for a bit and have found some things that work ok but there are some more fundamental flaws that have to be addressed to make it better. First I increased the base xp needed to go from level 1 to 2 but I decreased the multiplier for xp per level. Initially it is very close to what you guys have for the first few levels but it has a less drastic increase of xp needed per level allowing for more level ups without them becoming an exponential growth race. This leads into the root of the problem though which is risk versus reward. If you have a single champion with a group of trained units you get max xp for all, however once you add a second champion that rewarded xp drops drastically to an almost laughable amount. While I understand that champions are strong they do not warrent taking a 1/4 xp split for 2 and a 1/6 xp split for 3. What this does is removes part of the RPG aspect from your 4X game. Make it a minimum of 3 champions before you get an xp split reduction such that you can have an adventuring party. Then those 3 can bring along hirelings (trained troops) for additional power when needed. Finally lairs vs patrols and the risk rewards of new games needs to be looked at. I am personally of the opinion that a lair should NEVER be attempted at level 1. You should have more wandering low levels for the initial close type lairs for new champions to learn from and then once they become who they are can attempt those mini strongholds. Consider that a lair is a "city" for the monsters and while you might be able to take out a newly settled npc level 1 city would you rush into a level 2 city with green troops? So basically bump lairs harder but give them some smaller patrols but more of them to level off of for that classic RPG feel.
3a Suedo Champion Units
Alright last part, Henchmen and the special problem they represent. These are trained units that can then go on to have champions traits and paths as well as equip the most powerful gear. This and they have no xp split. While they have weaker initial stats they can become far more powerful in groups than any other unit in the game and at a minimal cost. This makes them a special problem because why would you use normal champions when you have access to them. After your initial champion every time you got 20 Fame just make a new Henchman. Also add in the problem that Henchmen get access to al the training buffs from Fortresses as well as essence which can eventually far outstrip a normal champion. Possible simple solution for henchmen is take away their ability to gain champion talents per level. They can still get everything else that is theirs and still fill a niche but not become replacement champions.
A long post but I think it covers a lot of problems.
