The best real-time strategy game I have played in my life. Takes a bit of decking around to figure out what all the stats mean and how to abuse them in a nice deck, but when you beat your friend in a 1vs1 its oh so sweet. Try reading The Art of War by Sun Tzu if you're having problems, its in audiobook form. And I suggest you get some friends to play with you, the ones that roam the public multiplayer games can be very good. Whereas if you have friends that are as noob as you are, then you can win some, then they win some as they adjust their approach, then you win some because you adjusted your approach, etc. This is very rewarding gameplay.
The game is known for being as close to realism as possible, and strategically it actually is. You have to supply your troops and ships with ammo and rockets if you have a prolonged engagement (so your ships in naval battles need supply ships as a part of your deck). You also have to use infrantry in forests and buildings to spot and sneak up on the enemy (you can't shoot what you can't see, though you can shoot artillery at suspected locations).
The battles are very intriguing. You can't just rush ahead, because to win you have to kill a certain number of points worth of units, but if too many of your own units die then the enemy wins because they killed enough units before you killed enough units. This gives a very real feeling, because you have to take care of your troops as you would in real life. Each unit you get killed is another set of points for the enemy. The trick is to make each exchange worth it, so you take more points than you lose in the engagement. This is tricky, but very rewarding gameplay.
Pros: Everything, the only thing missing is a pure city map (unless I missed it). Just about every military asset in the world worth its paint is in the game, and there's endless replayability because no two engagements are the same. No base setup, no tedious setup of power-stations and resource harvesters, no tech-tree to worry about, no real unit cap that you'll ever approach (except in naval battles), there's a counter for everything if you only have the presence of mind to get it out when you need it (and managed to fit it into your deck).
Cons: It can be overwhelming, because there's so much to figure out. But this can be negated by playing with someone who begins playing at the same time as you, then you're on equal ground and will win every other match against each other as you figure things out.