Man I love King of the Hill!  Hank is my hero!
I think the show is very funny and definitely a more low-key and subtle humor, not like Family Guy or South Park, which I don't find very funny at all.
I'm a very southern guy and where I'm from I know all kinds of people like the characters on King of the Hill.  I get a kick out of it because it speaks to me and reminds me of people, even though often it tries to poke fun at those kind of people a lot of the time and meant to be satirical.  But still, its nothing that offfends me and its a very funny show!