Nanner,
Why are you pointing out the name differences between drones and missles as if it means something? They are the same thing, from game to game. A drone by any other name impacts just as hard..

Apart from what you pointed out, Nanner, I have to agree with Scippy - SFC1 through OP were as faithful to SFB as the developers could manage with the transition to real time and the limitations of the engine. Granted, there are some departures, but most of them were not because the developers didn't feel like putting them in, or didn't want to make a totally SFB-based game, but because whatever wasn't there was too difficult to code in, especially in OP when Taldren had finally squeezed in as much stuff from SFB as they could successfully code.
SFC3 did walk away from a very large part of its old audience, and it was only saved because it attracted a new group of twitch gamers that were veterans of other arcade-y TNG games(no offense intended guys). I know of few in the D2 forum who even have SFC3, and of those, fewer still who still have it installed on their machines. I can't give you exact sales numbers on SFC3, as I don't work for Taldren/Activision, but I have heard that they were quite disappointing - less than both SFC2 and OP. I'd like to see the numbers as well, myself, as this is only what I've heard from outside sources.