I get the feeling the hate is more about the military failures than about character.
It'll be an interesting psych experiment to see how everyone reacts had Caleb invaded New Samarkand and saved the FS.
I don't think it's about the military failures so much as it is a reaction to what Caleb represents being thrust into the Battletech Universe.
Every faction, be it a House, Clan or Comstar, has a lecherous character somewhere in it's history. Until Caleb though, they were all either historical figures or minor characters of one sort or another. Had Caleb been a historical figure or a minor character, I don't think the reaction would have been as extreme as it has been, since his very existence could be overlooked or partially ignored for the sake of the story arc.
Caleb being the First Prince, however, forced the issue into the forefront of the audience's mind and, frankly, this type of character doesn't fit into the timeline as a primary, ongoing character. Even the villains that we've seen so far, which have been unsavory in the extreme, have not been on the same level as Caleb Davion. Even Mad Max, who pretty much set the bar for villains in the Battletech Universe, was evil in a cheesy 80's kind of way, which is why "Mad Max = Lo Pan" works so well.
Caleb, on the other hand, reminds you of something you'd see on the nightly news and that's a large part of the problem. We come into this universe to forget the problems of the present, not have them shoved in our faces. If I wanted that kind of evil, I'd just watch the news.
