Starts off good, then, gets too easy.
Towards the end, it got really, really easy. I didnt even have to click. Had about 200 shooters and 50 craftsmen and even silo workers to fire 1 rocket immediently after the other. The result? Total ownage. Make it harder. Consider adding more units as well, I mean, there were only soldiers, gunmen, rocketmen, jeeps and tanks. And in most cases I could sit back and relax.
Also my fort looked REALLY SHITTY after I finished the game. Even though I'd gotten max hp, it looked like shit. It looked like a 3 storey house with a brick wall, not a secure fort. Work on that. Needs more upgrades.
Gets way too easy.
P.S. Yes, the chaingun does ruin the game for you.