what would you do with the FF Rouges to update them?
Again, I wouldn't really change anything
about them, I'd just do new things with them. Put them in new situations that explore who they are and what they can do. Give them somebody to talk to.
Off the top of my head?:
Well, The Wizard, I guess, I'd try to distance him from Doom, the other and better known mad scientist who likes to one up Reed, by emphasizing his nature of, essentially, a cyberterrorist who's in it for the kicks. Emphasis his nature as a narcicist, maybe make him something on an anarchist. Definitely explore his psychology, figure out why he only ever seems to feel alive when he's using his intellect to make other people suffer and show his mastery of the technological age. Maybe have at least one storyline where he encounters the FF because he's racing them to a scientific find that he just wants to use to cause more trouble, sort of emphasize the difference between how he sees science and the natural world and how Reed and the rest of the FF see it. That might be a neat story.
With Diablo, I'd probably emphasize the horror elements of the character. I mean, his origin is that he sold his soul to the devil for magic powers. Seems like the kind of character you take in a horror direction. In his first story he manipulated The Thing and a bunch of people into working for him by making deals with them. You could maybe take the approach that he makes faustian deals with people because he himself went into one and is an unwilling servant of The Devil, so it gives him a sense of power and control in his life. So, you could have stories where he's manipulating people and turning them against each other and building this cult of loyal brainwashed followers around him, and then he gets a call from the man downstairs witha mission and finds himself in the role of the (highly empowered) lacky. There's actually a lot you could do there, now that I think about it. He's this highly empowered minion who loathes his possition but can't do anything about it, so he regains some of his indignity by doing what The Devil does to him to other people. Along with that core concept, you could do some cool stories with him just mind raping people for the fun of it, or trying to acquire some artifact or new discovery to increase his power and the power of his cult, and stories of him running missions for Mephisto. You could also start a story with just him as a cult leader and amp up the creep factor as the demonic elements start to come to the surface. He'd actually be a really good FF villain if you want to go a horror route.
With the Mole Man, I'd honestly just make him an uneasy ally of the FF. At this point they've done the "go down into Mole world and they fight, Mole Man attacks a human city for fun" stuff to death. They've already established in the comics that he's sworn off attacking the surface because he knows even his monsters can't beat the military and Earth's super heroes. Just have Mole Man be a total arrogant jerkass who non the less helps out the FF when they need to store **** underground or they have a new monster then need to get rid of in exchange for sharing technologies and getting a new monster to add to their collection. He'd actually make a nice supporting charactrer, and you could get into some nice stories of the political conflicts between him and Tyrannus.
The Puppet Master I actually kind of like. His past actions, including killing a man and then marrying his wife and adopting his daughter, make him seem like a really self absorbed, spiteful, obsesive person. You can do a lot with that, that can fuel a villain's motivations for quite a while. I think a good thing to do with him is have him use his mind control technology to manipulate his way into a powerful, cushy, but not too powerful possition in some government, maybe setting himself up witha very low possition but building up the infrastucture so that even the top dog answers to him, and really have him pull the strings with mind control and more subtle manipulations to gain more power and to just **** with people. Put him in that kind of possition of power, he might have some staying power. You could even write a storyline around that where he becomes a big bad.
Those are just the ones I can think of off the top of my head.