This is a tentative list; there's a lot of stuff I like about the game, but since I haven't played it for a few weeks now, I can't remember everything.And I know some of this will sound mean, but it's not meant to be. I wouldn't be here trying to help if I didn't care.
I like the resources in the game, and I think they work fine for the most part, but I think this can be improved on. I think it would be better if there's more resources, even if they're weaker, so the world map doesn't seem as barren (think Master of Magic style, where every tile gives a benefit). Maybe even have it so that when you "restore the land" (i.e. a city's influence zone) new resources are revealed instantly, without the need for a tech.
I like the graphics in the game, like the cloth map and the ability to zoom in and out. I would just say make this a bit smoother with improved performance and the ability to zoom in farther like it showed on some of the preview videos.
Sovereign customization is good, but it feels a bit shallow. Better and more useful options would help make your sovereign stand out and be more powerful.
I have to admit, I didn't like the fact that the tech tree was split into so many options, but now I do understand and like it the way it is; it makes sense and is useful. I like that I can just focus on adventuring if I want more heroes or more resources.
Ways to improve it: a lot of the techs you can unlock are pretty worthless, to be honest, and don't unlock almost anything. I would see about consolidating some of the technologies so they are more worthwhile. And another thing I noticed about the resource techs (in adventuring) is that if you research them early, you will not be retroactive (i.e. there should be many new resources in a map area that hasn't been explored if I have researched the resource tech early in the game). I'm noticing that currently if I research it early, only the area that I have explored will get any benefit. Any area that is still hidden will be just as barren as before.
Improvement: I was under the impression that the RARE techs were not going to show up very often at all, and would be insanely powerful. It's true they don't show up all the time but I am seeing them often. But, to be honest, they're pretty worthless right now. As it stands, I would not choose many of the rare techs if they were available, and would change tech trees instead if I had no other option. Make many more rare techs, and have them be very powerful with a significant benefit. Make them more expensive if you must, but they should "turn the tide" in a game.
I like the goodie huts, I like the quests. They are a good starting point for this game, and I'm sure they will be improved on as more patches come out. Improvements: MORE QUESTS AND ITEMS. I can't stress this enough. One of the things I can't stand about a game is seeing the same thing again and again. So, when I'm playing elemental, it's always the same quest, and it's always the same items I get: escort this person, kill those rats, you found a midnight stone, or an item to give you 1 essence (c'mon!). Think AoW: Shadow Magic or MoM style. You won't see the same items unless you play a few games. You need many more quests available at low level and high level, and with more variation. You need TONS more magical items in the game. Right now, there's the basic items and a few magical ones, that's it. Again (and I hate to keep bringing up MoM, but they did a good job with this) in MoM they have tons of items, some very powerful, some incredibly weak (which is good). In Elemental, where you can put items into so many different slots, why not have tons of magical items to go with it? It should not be easy to get them, of course. You should have to do a big fight, or a hard quest to get a good reward, but they should be there and there should be a big selection (randomized) of what you will see in a particular game.
That's all for now.