Good discussion.
I agree that many people who ARE 'rednecks' don't consider being called one a put-down. Many are proud to be rednecks.
I heard a man once - who considers himself redneck call another man an extreme redneck by calling him "ghetto redneck". Which just goes to show how words used specifically become more generalized for use, like 'bitch'.
I agree that 'breeder' isn't an insult to many straight people. If someone called me that I'd probably just blink and think, "Well, in context, yes I am."
I think, in many areas, the word 'bitch' has not so much been 'reclaimed' as been overused and thus its impact lessened. My close friends and I were calling each other bitches jokingly years before it became popular to do so. We noted that outside our very tight group, other women were offended when we called them that. In the years since, it's come to have a myriad of meanings, but mostly I only use it in the context of referring to a mean person - male or female.
Most of our insults are gender based and sexual and mostly geared toward being someone on the receiving end of being fucked (hence women and men who like being penetrated). So you can see who dominates the insult development.
Hence, why asshole, pussy, 'being someone's bitch', c--t and whore are worse insults than being a prick, dick or ball-breaking bitch.