Yay Jayne was fairly simplistic. The dude barely had any morality bc he was more animal than man. So in that way he played a "straight man" to Mal'a greater level of complexity? He even gave voice to what many of the others were thinking, including Mal himself, but they had the grace to not say it.

True evil requires a minimum amount of "character" in order to achieve anything at all - great or otherwise. So it's less like Jayne was "bad" and the government was "good", and more like Jayne was simplisticly animal-like, while the true evils rose up much higher. With great power comes great responsibility, or whatever.

Jayne is like a wall painting in the background - he's scenery?

As far as Whedon, I dunno, I like a lot of his works, I don't like his character. The two aren't entirely connected in my mind, though perhaps they should be more so, I just don't know.

On the other hand, wasn't all of this pretty much happening even while the show was still in production? You mentioned that it had "aged", so I wasn't coming at this from a perspective of bad show vs. good show, but from it having been a good show where something external caused its goodness to have tanked. If it had been bad at the start, then we wouldn't say that it "aged", just that the show sucked. Which it didn't... and yet, also... didn't it always though? That yin and yang seemed to me to have not been so much changed by the passage of time?

Edit: oh, I haven't heard of whatever has been revealed about the actor who plays Jayne. Maybe that's what you meant. It might change my own perspective of the show in that case. I would hope not actually... but it might.