Crowley, Dracula, and Rasputin are good, solid, villains. That said, having the other two minions of Crowley? Probably a bad call. Of the three, he's youngest and in all likelihood least personally scary. And having them manipulate just Hitler is a bit off. Having, say, Crowley manipulating the British, Dracula the Nazis, and Raputin the Russians in a similar fashion is a bit more plausible and expands the scope of their plan...and provide globetrotting fun as they investigate each segment of the plot, or time pressure as they strive to disrupt a meeting between the three.
In terms of PCs, John Coffey's debatably a bad choice due to being from fiction about the era, not fiction from the era (unlike the original League), though if you're opening that door, Indiana Jones might be a cool addition. Doc Savage also seems like a must if you're going pulp...though perhaps overpowered, so I suppose a reference might be sufficient. Are these from your players directly? If so, it's not a bad lineup, but not an ideal one either...if not, I'd leave it up to them, people all have their favorite characters, after all.