Why do we think villains should just look difficult?
I guess BLADE has his innocent face with terror in his mind. BLADE, is a teenage guy who took interest in hacking and learning new things with an evil perspective. For him, coding is just like a toy, and barging into someone's personal data is fun. He became a youngest most-wanted criminal when he delibrately hacked into military websites. BLADE has his own reputation in the world of hackers - famous for not leaving any clues behind, notorious for reverting all infractions on who-ever accuses.
And what if he messes with J.A.R.V.I.S.?
Imagine Iron-man has no support of J.A.R.V.I.S. as BLADE has got full control over him (J.A.R.V.I.S.)
BLADE used the arc reactor power to design his vehicle - a hover board! With powerful authentication, the hover-board fortunately or unfortunately recognizes only BLADE; only he knows how! Besides, no-one else can lift it as it generates sufficient energy to provide an opposing force to the person trying to lift it. Maybe, it's design is such that it has no place to have grip on to lift it.
How does BLADE lift it?
He never lifts it, all he has to do is stand on it and it starts floating!
BLADE emphasizes to terrorize people, how to stop him?