Specter is a Woobie, Destroyer of Worlds
He was always very intelligent, pretty much on the level of a human, but was still considered a lesser creature and forced to perform for other humans at the monkey park. He's not really evil, he's just misguided and thinks Humans Are Bastards, and wants to prove himself to a world that wouldn't treat him as an equal.
- Most of this became true in the Playstation Move reboot, oddly enough. Just replace the backstory of him being a circus monkey with that of a astronaut monkey and you're spot on! Not so sure about the original games though...
Monkey White is Cranky Kong.
Think about it. Both of them are old, crotchety primates who are genius inventors. White's metal diaper/pants thingy could be futuristic leg support as opposed to Cranky's two canes.