Criticism: Underdog destroys vastly overpowered opponent because the story demands it.
Answer: You can tackle this one in several ways:
1) Just say that "it was a raid". Doesn't matter that you have vast armies clashing against each other, if it was a raid, then you can do anything.
2) Point to people who accomplished amazing things in real life, and use this as your excuse no matter how different the circumstances are.
Criticism: Character does a complete 180 and changes his motivations between SC1 & SC2, while losing several IQ points in the process.
Answer: No problem. Just use the all-purpose "it was 4 years" excuse. It's enough to justify anything.
Criticism: SC2 now features dragonball z fights, magical "essence" nonsense, and other crap that belongs in fantasy instead of sci-fi.
Answer: Just regurgitate that "Any sufficiently advanced technology is indistinguishable from magic."
Criticism: Numerous and blatant retcons.
Answer: Deny the existence of retcons.
Criticism: SC2 has any sort of flaw whatsoever.
Answer: Easy. Just mindlessly regurgitate that "Brood War did it too". Clearly, if flaws exist in Brood War, then that instantly invalidates any criticism you can level against Wings of Liberty. Make obtuse references to "nostalgia" as the reason for why nobody can look past all the plotholes and nonsequiturs of your favorite game. After all, no matter how bad the story gets, it can't be worse than Brood War.
Any questions? If so, read this: