Hi,
Imho, elemental has the basis for a good game, howwever, it lacks replay value. The same strategy can be used to win every game, every time, even at extreme level. It doesn't matter if you're playing kingdom or empire. Choosing a less than optimal starting position intentionally is not my idea of increasing replay value.
So, some suggestions for making the game more interesting:
1. The "single unit vs a horde and not getting hit" has got to go. Researching defense and offense to get war staff and leather armor and designing a unit with maxed att/def will create a tank that can kill just about anything the opponents throw at you for the first couple hundred turns. An increased chance to hit and do minimal damage so that several weak units can attack one strong would improve this. Or/and: Once Team has been researched, it should be possible to join several small units into a team (not having to build one from scratch), also team should be earlier in the tech tree.
2. Specific buildings/units/abilities for each race. As it is, everyone gets the same tech, the same weapons, the same buildings = everyone can employ the same strategy to win, every time = boring.. Solution: Add benefits to each race that skews their tech tree in different directions altering the usefulness of different techs. For example, Resoln could have +5 att when its troop uses cutting weapons, Capitar gets +5 def when using plate armor or whatever.
3. Different weapons/spells should do different damage vs various types of defense. The dodge feature is one step in the right direction but it would be nice if, for example: Cutting weapons do more damage vs leather armor, blunt weapons do more damage vs plate armor, ranged weapons do more damage vs leather armor and disregards dodge, fire spells do more damage vs heavy armor etc etc etc. Combined with suggestion 2 above this would make some races focus on "their" best sides, and create replay value for us in that different races will require different strategies to beat or win with when playing them.
4. Race specific strategic/tactical spells. As it is, I've played dozens of games and I've still to use Curgens inferno, earthquake etc. Why bother? By the time I get to them my hero is so strong that the only reason my opponents are still alive is that I'm still curious about the tech tree. I can wipe out anything on the map with impunity anyway. Some nice strategics spells that create different bonuses/penalties inside my zone of influence would be nice .. for example a spell that renders ranged weapons less useful, a spell that increases all my tropps att, a spell that poisons any opponent entering my land etc etc.
5. Game AI, and this is most important. The AI is way, way too passive. I seize the initiative straight away and the game is usually settled after playing for 30 mins .. after that it's just a cleanup action. In a typical game I usually wipe out one or two opponents, grow my my empire to 2-3 times the size of the next biggest opponent .. and then they want to make friends with me?? Who in their right mind would want to make friends with a homicidal maniac 3 times your size?? It's supposed to be WAR! One way to increase the challenge of the end game is to tell the smaller empires to band together to create bigger empires that might be a match for me, and of course, to make them much, much more aggressive. The logic being, that in a war to the death noone wants to be on the losing side.. 
Thank you for your attention,
T