Something that greatly attributed to FS2 IMO was the quality and depth of the voice acting. When the last survivor of Kappa wing emerged, warning the GTVA to get back and shut down the portal, and for command to classify the whole thing 'level phi', it certainly put a shiver down my spine.
Adminral Petrach had an authorative, yet fatherly and all knowing sound about it. Something that made want to pilot all the more vigorously and harder just because hes telling you whats at stake.
The C.O of the Colossus had a sound in his voice that you couldn't help but smile when he came into the field of battle. If there is any definition of 'the cavalry arriving' , its the GTVA Colossus warping in from subspace and putting 4 beam cannon holes through the NTCv Hawkwood.
And as for 'command', well it was always there....not. It was there to say 'help is on the way', when it came too late. To tell you your mission, to shut up that pilot who was irritating you, and to give you that health warning
"Those cruisers have anti-fighter beams with an effective range of 1500 metres. Lure the escort AWAY from the cruisers BEFORE you engage." Certainly some healthy advice.
And Snipes....well, possibly one of the best.
All in all, I think you'd all agree that voice acting contributed much to the success of FS2. Unfortunately , space-sims never had a great appeal to many. If a company took up the rights to make a FS3 , and made it, well, i think it'd sell much better now then it FS2 did.
But then again, its all IMO.
