Ninjas (Preferably the Tick variety, so touch of death and cheese)
Stormtroopers (preferably Star Wars and they can’t shoot straight)
GI Joe: Cobra Commander
GUNS! GUNS! GUNS! (Ray guns, plasma guns, bolt guns, BFGs)
The best practice advice I have for writing card carrying Saturday Morning Cartoon villains is pick something, a real life group, a trope, a somewhat sane (or cheesy) villain in another show or comic that you have always wanted to mock, blow them up out of proportion and run with it.
The key is have fun. At that point, you’re ultimately more beholden to the rules you set up (and break) along with the conventions of the genre. I mean, your card carrying villains could be Calvin and Hobbes style snowmen who want to transform the world into a winter wasteland through a series of cleverly staged snowball fights.
Roll with it!
(I’d be careful to avoid any Matrix/”I know Kung Fu” gags.) Sticking with a stand in that plays off cultural memes is usually a good idea.
Play Warhammer 40k Space Marine and see if it gets you in the right mood. The goal is to be as silly as possible, then roll over to menacing before going back to silly.