Company of Heroes
The RTS Company of Heroes has an unusual economic model where, instead of spending time building resource collectors and upgrading them, you focus on capturing territory and fortifying them against the enemy overrunning them.
Because of this focus on territory-as-resource-generator, the action builds quickly into a frenetic back-and-forth with front lines constantly shifting. If you can manage to make a foothold in a territory, you can occupy random buildings and turn them into forward operating bases that can heal your wounded troops and build reinforcements. If your enemy can't get you to abandon those occupied buildings through superior force, he can roll in some tanks or bazookas and turn them into rubble. Buildings are finite so that's usually a last resort.
Each side is naturally different from the other (unlike games such as SupCom) and you can further specialize based on how you perceive your opponent will play the map or how you prefer to attack. Since often you won't know how this plays out until you all reach the top of your tech trees, you will have to learn how to use those differences to your advantage.
There's a lot to say about this game but I would suggest you just give it a spin and see if it's for you. If you want to play, send me an email. I like to play either against people or with people against CPUs.