I've been working on a shoot-em-up called Bolt Action for the last 3-4 months. I didn't want to make an overly frenetic shooter, but it feels like I whimped out code-wise in that the guns are bolt action and there aren't mass amounts of bullets flying everywhere. My lame justification is that complexity is going into other areas like environment damage and sheer number of bad guys.
The base of the game is completed, though I'd say 5-6 months before I have something worthy of putting up on here for critique and maybe 10 months before I'm done with it. Progress is slow due to me not being in a big hurry and I'm enjoying learning AGS in the process.