I could prefer to start discussing about RBY UU's Pokémon, how good or bad are them on the UU's and OU's metagame, what improved on some to make them arise on the future, and what did make them worst with the time. The GCS's OU is not a bad idea, but that could exclude the RBY metagame (something I could like to not being excluded, yet), but well, it's just my opinion. Oh, yeah, and include they posterior evolutions, too, like Golbat/Crobat, Seadra/Kingdra, and stuff.
I love Caterpie, he's a so adorable little bug! ♥ (Also, sorry for my English, I'm still learning it and I'm not a native speaker).