Don't change a damn thing about them and just give people more of what they like about these properties?
Make more theatrical tom and jerry shorts?
Update these shows to function with new technology and just make more of them?
I guess the honeymooners thing with flintstones is a little outdated, but I think people would be receptive if its about adult stuff like it was, originally. Maybe make it a double feature with jetsons.
Yogi bear's setup seems pretty timeless desu. Scooby doo hasnt changed the status quo in decades and its still trucking.
Just give top cat to the mexicans, give it to studio anima or something, they genuinely appreciate it more.
They already tried to reboot johnny quest but with venture bros around it seems pretty redundant. They could make a spiritual sequel with updated technology and a grown up johnny, I guess.
Huckleberry hound always kinda sucked, he's better as a sort of host for all these other hanna barbera characters. Maybe they should bring back banana splits and embrace the outdated psychedellic charm?
Quickdraw mcgraw seems limited by the setting, maybe put him in genre stuff. Like one episode he's a noir detective, the next an action hero, etc.
Snagglepuss just seems odd and I've got nothing.
They should reboot atom ant in the style of that cn groovy, at least as a miniseries.
they already rebooted space ghost into a weird comedy show and the new comics. Maybe they could take some of their other action stuff and rework it into an action block. New herculoids and thundarr would be cool.
the fact that wacky races and dick dastardly as a character have been ignored is a crime.
Honestly, the thing with these legacy characters is that if they become iconic and don't have a lot of depth to them, it doesn't make a lot of sense to change them too drastically. You just need new teams to add on to them and make them better and appeal to some modern sensibilities here and there.