Half the cast of Firefly kicking Covenant ass? I think yes.
Love this game to death. Great atmosphere, due to lighting, VISR, and the moody OST. Never got into too much Firefight (no-one to play with due to no Live for a long time), but what I played of it was intense fun. Wish there'd been a follow-up.
I'd like to hold off waves of Flood and Covenant badasses in The Maw. Not sure exactly where, though.
Either way, a never-ending, three-sided fight between you, The Flood, and The Covenant forces would be ideal for me.