I have to say that the characters Vince gave these guys are far more memorable, and far more exciting, than their original personalities ever could be.
Without the gold paint, and the creepy music, and the creepy mannerisms, Dustin Rhodes would just be...Dustin Rhodes. He would be the son of one of the best performers ever, a big goofy-looking good-ole' boy who would be forever compared to his daddy. See, WCW tried to make him legitimate by just letting him be himself. It didn't work. So Vince and the creative team saw fit to change him up and it worked for the better. Dustin Rhodes will forever be the black sheep of the Rhodes family, simply because he was Goldust.
Gregory Helms had moderate success as himself in WCW, with some solid reigns as the Cruiserweight champ and such. When he came to WWE during the Invasion angle, he was as bland as you could be, in a company with some electric performers (The Rock, Stone Cold, Jericho, etc.). So he dropped the Cruiserweight belt to Billy Kidman. And he was going nowhere...until Austin spotted his Green Lantern tattoo. And history was made. Years down the road, they tried letting him be himself again and even gave him the Cruiserweight belt to hold on to forever. While I personally thought he had a good character, it never caught on with the audience I think.
So in all, Rhodes and Helms are to be remembered, in the annals of wrestling history, as their outlandish characters and not as themselves. It is just a stigma they will forever be stuck with, but I'm pretty sure they don't mind as long as they are making the big bucks.