When I first saw this show, I couldn't stand it. Neither could anybody else I could find. It was a case of "I like everything BUT this show".
As time went by, however, I grew to appreciate its down to earth, yet sometimes subversive plotlines, and the fact that its characters' mundanity is what made them interesting.
Quite obviously influenced by and pitched against 'Simpsons' (and later, 'Family Guy'), 'King of the Hill' does a double-dip because it comes across as both redneck and 'alternative' at the same time. It's about a typical, fault-ridden suburban family, and is set in Texas, which probably makes it about as topical as you could get just now - yet KotH eschews the overt political satire of 'Simpsons', 'Family Guy' or 'South Park', and concentrates more on the narrower focus of the characters themselves.
When I first saw this, I thought it was one of the ugliest looking shows in recent memory. Now I suspect that ugliness is more specifically 'plainess'. This is a warts and all version of 'Simpsons' or 'Family Guy', and while it perhaps fails to reach the hyperbolic heights of those shows at their best, ultimately it's surprisingly endearing if you stick with it.