Right. Last night when I went to bed, I got around to think about some things that might be an idea to implement in elemental:

 - As it stands right now, champions and heroes aren't up to par with other units. They don't feel special. I suggest you buff specialities, and maybe even make some new and interesting ones. Besides that, you should make these scale with level, so it pays off to get your heroes into the field to earn some exp.

That said, MoM had a system, wherein your heroes would gain experience by just being in the game. Elemental could benefit from this type of system as well... Make your heroes gain 1 xp/turn, either forever, or up to a certain level.

If heroes or champions get too powerful, you can always limit the amount you can have at one time. Maybe even tie this to an adventuring tech, that can increase the amount of heroes you can control at one time.

 - I was working out a way to get an enchanting system into the game. I haven't thought it through completely, but I do have some basic concepts:

Whenever you can start getting those first minor magical items, you can begin enchanting

Enchanting takes time, costs money, crystals, and whatever the item you're enchanting costs to make

Only a channeler can enchant, and he needs to be in a settlement that has the Magical Forge improvement (new improvement)

What you can enchant items with, are dependent on the spells you know. Each spell has a particular effect on items (when used to enchant) that relates to what they do when cast, but it's a different parimeter. (list will be posted with pastebin below as I make it)

You can only enchant an item you can already make, and you have to produce said item in the process (hence the extra cost of materials/gold)

The time it takes to enchant an item is dependent on the amount of spells you enchant it with. (spell cost is 5+half the cost of the spell cast). If the channeler does not have enough mana to make the enchant in one turn, his mana regeneration rate could be doubled (balance tweak), but he will continue the enchanting until he/she has cast all the spells (think of this as a ritual, in which you drain mana over turns).

The amount of spells you can enchant an item with is equal to the channeler's essence/10 rounded up (so a channeler with 22 essence can enchant an item with 3 spells).

The channeler gets a moderate experience reward after the enchantment is done, depending on the power of the enchantment.

http://pastebin.ca/1925873 <- enchanting spell list.

 - More variety in item rewards from adventuring: As of now, I've seen very few interesting items from adventuring. This could, of course, be done easily with the enchanting system above, where the amount of essence and mana required would determine the difficulty to obtain the items. You could maybe even make artifacts that would be very difficult (or even impossible) to make with the enchanting system above. I'm especially missing equipment that suits pure spellcasters (mana regen multipliers on items, int and essence on items, etc.)

- Magic resistance (resistance): As it is now, it seems that defense also determines how well you do against spells. This isn't a good thing. The system I'm suggesting here is very simple. A stat that isn't dependent on anything, that is a percentage chance to avoid spells, or take the full damage from them. Maybe you can even make a faction trait, that gives 5% resistance to all your troops. There could be items that augment your resistance, as well as potions (like the .5 essence potion, only with +1-5% resistance). Of course, there should be a hard cap on the amount of resistance you could get, or it would overpower players who focus on magic. Maybe you could even make spells that sacrifices effectiveness, in order to ignore resistance, or a spell that lowers resistance of a unit or an area for the remainder of combat.