The long, hard, scary time consuming feature is the AI. It’s the one feature that could delay the game beyond August 24th.
Personally less than 3 months from now seems way to soon. Maybe you guys can get the game done by then but what about testing, polish and balance. There are huge things that are barely in the game or completely non-existant (tactical combat and magic) that can have huge impacts. I have no experience with this so hopefully your judgement is correct but February sounds like a much better time frame to me.
This is addressed to pretty much everyone who is thinking along this line:
How much "beta testing" were you part of for Spore? Or The Sims? Or Civilization IV? Or what have you?
Don't assume because we have public betas that somehow those public betas are somehow representative of the full project.
Every public beta (every. single. one) that I've done -- going back to 1993 with the OS/2 version of Galactic Civilizations has had this same thing go on.
As other game developers can tell you, the actual "game" is maybe 10% of the total project in terms of engineering hours.
Back in 1994, I made Star Emperor over a weekend - by myself (more here). That 2 day period included modifying the AI for the different game mechanics, a new user interface, new game mechanics, new screens, etc. Two days. The game went on to be a big hit. (Star Emperor was basically Warlords in space).
The point is, what takes actual TIME in game development isn't the game. It's the assets and engine. Spending 3 months on "polishing" or "balance" would be, literally, insane.
What typically delays a game are stability and missing features. Stability is something I'm pretty confident in nailing long before we go gold and other than the AI, the features are in. Internally, we're in polish and balance mode already and awaiting beta 2 and 3 for more feedback.