Hi there.
Most suggestions in this thread has probably already been discussed in some way or the other. I have nevertheless choosen to put forward my ideas here for two reasons: 1) perhaps some of my ideas/concerns have not been discussed 2) It never hurts to read through some suggestions two times.
Firs off I think the more scarce initial world is a good thing (that is until adventuring techs are researched)! That being said there is a lot of issues with Elemental (which by the way holds so MUCH untapped potential, damn this game could become one of the greatest!)
My first concern is skills: When you recruit champions (who by the way seems a little underpowered) they often come with some nice skill like crushing blow (Adventurer). This is really nice except you cannot use that skill as it costs mana! Some champions on the other hand come with passive skills like vengeance making them a lot better as this skills acutally applies - Skills like crushing blow, dominate etc. should be utilizeable!
Some of the skills need tweaking. Fx. I obtained Marug the dragon in my current game and of course this Dragon should be a massive unit, but it is however to massive (21,6 essence, firebreath and dragon fire). I mean Dragon fire did 96 hp of damage to a unit with 15 armor = Instant kill, and it only costs 3 mana. Crushing blow is also overpowered I think (when you actually have accces to it) or actually the HP of most units are perhaps to low.
More skills should be added: Leadership (bonus to morale in army), Diplomat (production of DC points). You could also add units with limited spellbook acces (fx. units able to cast fire dart but nothing else).
During my game I also noticed that units have different restrictions on equipment. My sovereign (adventurer) cannot equip alzors armor, journeymans cloak and pressed breastplate (no one seems to be able to fit that kind of armor). I actually like restrictions on some kind of equipment (except for the sovereign) but make it skill dependent then (this armor requires 15 str to equip etc.) that would make hero specialization more fun. And more different equipment (and equipment techs) would be welcome in my opinion.
Sovereigns are way to underpowered. I mean lvl 6 sovereign 23 hp, 15 att, 22 def, 16 mana (could have been 19) and 18 int. Come on, he should be badass at lvl 6. I am also concerned that I reached lvl 6 before any of my children grew up = lvl 1 child (already outdated).
Techs are researched to fast in my opinion (normal pacing). In my current game I married in the 10th turn or such. My first daughter has grown up and I have already researched at least 70% of all techs (1 lost library and 5 cities in total - 3 of them was founded in the last 30 turns). Make each tech more desireable by taking longer to research! In my game spells are researched at a balanced level, but I do not of course control a arcane labratory resource (or whatever they are called).
Dynasties should come into play earlier in game (not necesarily earlier in absolute time, but at an earlier technological state instead of at a point where most research has been conducted).
GOLD mine vs adventuring. If you wanny earn money go for adventure techs and just ignore cities most of the times. In my game a ridicoulous number of treasure chest (100-400 gildars most often) was spawned. In comparison a gold mine produces 5 gildars per turn. I earned 3000 gildars on treasure chests in approx 30 turns. That needs balancing! Plus adventure techs spawn more powerfull monsters which disrupts other players concentrating on warfare/city building as well! Further it gives you acces to creatures like dragons (with a little luck). Adventuring is very very overpowered in my opinion! Perhaps some areas of the map should be treasure/monster intensive - powercentres of the old world attracts monsters or something like that. This would also make it somewhat easier for warfare players to launch attacks on opponents without having to battle all kinds of nasty monsters on their way in late game. Techs that increased the value of gold mines (instead of the amount) would be welcome. I must say I also liked the earlier beta version where resources like bee-hives existed from the start, but you needed to research some tech in order to utilize them. This meant planning and potential fighting over areas which could at a later point become very valuable. Some resources could also have multiple variables like +5 gold and +5 materials (marble pit fx).
Improved naval would be a nice addition. More ships, seamonsters etc. You could also add hereos with naval abilities (admirality - increased movement/naval str or some skills enabling ships to do certain things like boarding etc.). Maps with more islands.
Being able to build fortresses on strategic locations would be nice. These could perhaps also serve to help you clearing your roads for monsters instead of constantly having to rid them of monsters attacking caravans.
Tapping of resources outside influence area without having to build a city (perhaps this is possible? I just do not know how).
I also noticed that researching 1 tech in any tech tree requires the same "effort" if the tech level in that tree is the same. This means that you will blaze through diplomacy more quickly than warfare (counting "refined" techs out) - this should be balanced to some degree I think.
When you defeat another hero/sovereign you do not get acces to his equipment or at least a chance to get hold of it (most of it could be broken or something). Artifacts should play a more prominent role I think!
Healing nectar is also overpowered. Just take 10 of those with you and you have a major advantage.
Factions abilities are unbalanced (at least if you compare them using the faction creater tool).
Neutral factions (at least in my games) are always placed next to an ogre camp (1 was placed next to nothing) - which I cannot use as a Kingdom! Also when I capure a city I cannot expand its area of influence no matter what I do!!! Also you cannot negotiate with these factions and they play no role at alll except lying there doing nothing.
You should be able to demolish captured citites (over time - not instantly. Capital cities should not be razeable. High level cities should perhaps not either or at least take a significant time to demolish)
That being said I still think elemental is a very fun game, but I am discontent with that huge amount of potential lying there untapped! I am however confident that Stardock will turn this game into the best 4x game ever in time.