Really "Animated"
It would look good in an animation, but in this design, Mastermind design has become his character. What made his personality seem so funny was how serious, evil, and devious he looked, then, when you actual heard him, he was a complete idiot. Here, you have his design matching his personality, making it somewhat predictable.
This kind of reminds of what they did to (Crash Bandicoot) Tiny the Tiger (not exactly but similar). His name said Tiny, but he looked like a rabid tiger, ferocious, and evil, completely contradicting his name, then from "Crash of the Titans" onward, Tiny's design now looks like a tiger, wearing an army outfit, with a prissy little voice, making him one of those homosexual army men, therefore destroying him, nobody likes the new tiny, nobody.
So in this case, instead of contradicting the name with the appearance, leaving some humor, (for Tiny) this new design of mastermind completely destroys the mystery within his appearance, which makes him funny.
I personally think you should keep it the way it is, I actually find it more funny that since the characters look so damn serious.
Don't get me wrong the design is good, but it wouldn't the best idea to change it with the current, more familiar one.
Awesome Job,