A tie between Disney and Nickelodeon. Both of these stations offered variety years ago. Disney had stuff for pre-schoolers, older kids, teens, and adults. The station now seems to only cater to teens. They don't even show the old "classic" Disney shows anymore, like the original Mickey Mouse Club or even the concerts they'd show every Sunday night. One time I remember coming across a Billy Joel concert (which would probably appeal to adults more so than kids).
As for Nickelodeon, it shows too many Nicktoons and too many Teen Shows. At least in earlier days of Nick and even in the 90s, Nickelodeon was more balanced and had some variety. It had game shows, somewhat teen oriented shows, kid-oriented, family shows, pre-school shows, foreign shows, educational shows, etc. I can't truly explain it, but Nickelodeon was more tolerable back then, imo Seems that now-a-days, in order to enjoy the station, you have to either be really young (Nick Jr), or a "teen" (seemingly everything else). It seems they've forgotten their own slogan..."Nick is kids!" =P