Granted, there are similarities between Eleven and Ten. Both of them are
Eleven, however, doesn't care what you think of him so long as you listen to what he has to say. So what if he eats fish sticks with custard, or barges into rooms and just uses other people's stuff, or just randomly talks to strangers, or changes his clothes in public? He knows he's the smartest guy in the room, knows what he's doing, and all he asks from people is to just trust him. What's more, Eleven pretty much flies by the seat-of-his-pants, adapting to the situation accordingly and stubbornly sticking to whatever plan he has in mind. If it doesn't work, he just goes, "Okay, plan B." At least that's the impression I got from Matt Smith's portrayal.