As usual, such an inspecific question cannot warrant a good answer. You have to explain what sort of box we are talking about here.
Everybody should feel comfortable being who they are. You should not try to be somebody you are not. (Oscar Wilde once said “Be yourself, everybody else is taken”) However, you have to define who you are, and that is where your question begins.
(In other words, you shouldn’t be doing things because others do, and you don’t have the strength of character to stop, you should be doing them because you want to or feel you have to).
What you want to do in regards to in/out the box is obviously dependant on every case on its own merits.
And being out-the-box purely for the reason of not-being-in-the-box – that is ???? ?? ??????, and the rebellious streak that is wron. Being out-the-box because you are isn’t as terrible. (Although “who-you-are” might dictate that you want to be in-the-box, but like I said, we need specific scenarios for that)