Every rule has an exception, and to be fair KOTH does star a family. Just not wacky off the wall humor, and how that type of show stayed on the air for 12 years is a blessing.
These voices actors are the characters, they bring them to life and give them personality and quirks. Maybe its just the Futurama gang trolling for some free publicity, but if its not and they really walk away, that's just sad on both parts. And good luck finding new VAs if this falls through, no one's going to risk their friendships for a little bit of money.