The Total War Mod is, in my opinion, the best. More immersive & complex than Hearts of Oak, but not quite the monstrosity that is BlackIce. It deserves a look-see by your team. Fully Man the Guns/Hydra compatible.
To all those who have never heard of or played this game: It is VERY good. I don't think you'll be disappointed. The developers seem to have a passion & devotion to making it even better. I think April 8th is the current release date for the expansion, US Marines.