Now that I think about it, any of the kids could do much more with their power. Fine, "heart" can control animals. But then we have earthquakes, hurricanes, tsunamis and whatever flamey shit fire can do. Basically if we drop the limitations of the user not willing to go all out, they all get buffed and "heart" still sounds underpowered. Unless it can control human minds too, now we're talking!
There was a "power glove" episode that did this i think? It gave whichever ring bearer who had it like 100x power with their ring. Of course it was evil, and i want to say it was mai tai and the "heart" ring that won the day, but I can't be assed to find the episode to make sure.
They could definitely redo this show with a modern angle focusing on the real villain causing pollution: capitalist interests. Too often the bad guys in captain planet were actual monsters trying to pollute because "blah blah we're evil".