Just trying to see if any of this occured in US-generated animation and, if so, when.
I'm using lineups like Boomerang and Jetix as an early guide. Going way back, there's nothing all that disproportionate in H-B stuff like Flintstones, Jetsons, Scooby-Doo, Josie & the Pussycats, etc.
But if you look at Marvel's offerings, there's a bit more of what we're talking about. Not so much in the first go-round (60s/early 70s), but look at the "evolution" of Sue Storm even between the two seasons of the 1994-5 incarnation:
I won't include She-Hulk because -- let's face it, everything's bigger when you're green.
There's even a little bit in Firestar the 1982 "Spider-Man and His Amazing Friends" show:
But Marvel really hit the gas pedal with the Fox Kids X-Men series. Storm, Rogue and Jean Grey/Phoenix weren't drawn with much conservatism.