OMG WALL OF TEXT!!! TAKE COVER!!!
As I've played it for some time rather avidly, I can add to this thread. It's however based on the newest version with the expansion pack included, which changes the game for the better. And it concerns the multiplayer. Singleplayer isn't really that good.
This game is about economy in a very, very big way. Due to the resource system, a player can only be good if he's as efficient in this regard as possible. That means using up all your resource income as it comes, not letting supplies acumulate, and, not using up too much, since that will stall all the fabrication, will power down shield, stealth fields, artilery and radars. Dmitron says he spammed power gens. The trick is not to overinvest in infrastructure of any kind too, since all that mass and energy could be turned into units. Spare power generators don't shoot, take up space and unit cap.
Resources can also be aquired from stones, trees, ruins and wrecks left on a battlefield.
Battles can be waged over particulary rich wreck fields. One can reclaim them even if no storage space is left, which means that it goes to waste, if there's danger of it falling into enemy hands... The complexity and extreme importance of economy in this game opens a lot of viable strategies. The economical part can be summarised easily by what banks try to do, that is stay financialy fluid- do not let spare cash to accumulate, have it work, or someone will grow faster than you, and don't ever have not enough to cover your expenses. Putting this simple rule into practice in this game is difficult and challenging, especially as the match progresses. But mastering it gives a lot of satisfaction and will win the game versus most inefficient opponents.
There are many, many units available. There are factional differences that influence the way those units are used tactically, ie on the battlefield, microing them. The sheer number of different units and structures creates a lot of possibilities. No point in going into detail, but there are many unorthodox uses that can be made of them, some leading directly to winning the game. It's not a mindless unit spam, although that can win games against less skilled players, which can be said about any RTS.
Commander is special. If he's destroyed, the game is lost. He is vastly more durable and destructve than anything available early in the game, which prevents games ending by rush after a few minutes. There are many upgrades that can be fitted on it, some having economic funtions, other engineering use, support functions for units in the field, UEF can fit a nuke launcher on it for example, Aeon can slap a teleporter. There are also guns n' armor. Later in the game he can be destroyed rather easily and will not linger in the field, sitting behind layered shields and defences, which forces the game to escalate. I feel this whole aspect is done very well.
Unit ballance is for the most part done well, partly because all four sides [counting the seraphim from the expansion] have simmilar units. There are two imbalances.
One is that Tier 3 air units are relatively very powerful, although that is mainly in one single role- assasinating enemy commanders in multiplayer games. Commander's destruction means you loose and that's fine, since it shapes game dynamics in an interesting way. Nevertheless, powerful Tier 3 air makes it a bit too easy to win with one surgical strike.
The other is experimental units. They are you usual sort of gargantuan over the top war machines, like huge tracked battleship-thing with a factory on it's deck or a massive flying saucer a'la the Independence Day, death ray included. They are usefull and serve to make the game more spectacular, to make it more dynamic while players progress up the tech tree and get more powerful defences and to make it a bit less exclusively about hundreds upon hundreds of units. This, they do very well. However, manufacturing them requires a lot of time and a LOT of resources, so they don't feature prominently in most multiplayer games. And that's good, because GPG have not payed to much attention to their ballance. Some are simply way to cheap resource-wise and build time-wise for their strenght and usefulness. However, due to their end-game status, they tend not to spoil the vast majority of matches.
Unit balance seems terribly skewed. My units get destroyed by enemy turrets with 1-2 shots, but my commander unit can walk in an wreak havoc and then just walk away and auto heal.
That's not skewed. Commander has to be tough. And while you retreated to heal any sane player would at least reclaim the ruins and wrecks and rebuild the damage you did, for the cost of you commander's valuable hp, rendering it vulnerable and out of action for some time.
Turrets are powerful, otherwise they would be meaningless when confronted with the number of units players throw at each other. Defensive structures in this RTS can actually defend stuff. However, you could have destroyed them easily with
1)artilery, mobile or stationary
2)mobile shields
3)mobile stealth in case of Cybrans
4)air
5)stationary or mobile missile launchers
6)cripple it by taking out his radar
7)cripple his radar by taking out his power gens
The list goes on
The bottom line is, I dearly like this game- it's my favourite RTS still, although I don't play it anymore. It's very easy to learn, but hugely difficult to master. It seems to be just a simple affair of spamming units, but it ceases to be once you begin see the possibilities. It's not mainstream by any means,
and most people will not like it.