@ Munx, Skiper, Marcio
Do not be that conservative. Missions could be great fun if only the bots would obey one's orders. Hiring new men [with individual combat values] and buying new equipment between the missions, like in the SWAT series, could sum it all up to a great singleplayer mode.
Of course the buying could also be done when the mission starts, just like in normal matches, but who wants to depend on the bots' choice of weapons?