Change Regular Character to Viper?

This may sound a bit un-realistic but i was thinking if we could change how guns look and how they perform, why can't we do that with characters?
I know this may sound very hard, but im just being curious and open minded.

Because it's not like you can see yourself, What's the point? You might see other people as viper, but what's the point? It's not like it'll let you buy Spec things, or make it harder for people to shoot you.

That's true. And i don't think you can run faster either.