Found The Real Ghostbusters while clicking through netflix for something to watch. Lorenzo Music as Peter Venkman. For all the cartoons I watched as a kid, he's the only voice actor from back then who I can identify just from his voice alone.
Casey Kasem - Most familiar being Shaggy from Scooby Doo; but also easily spotted on Josie and the Pussycats as Alex (their manager), and dozens of Superfriends episodes as the voice of Robin.