Don't focus entirely on Rose. The worst Tens I've seen are the ones who just post about Rose, who focus on shipping with Rose, who do so much with Rose that they don't delve fully into the game. And yes, I know that Ten himself is ridiculously obsessed with Rose, but don't make his characterization rely entirely on her.
And realize that Ten isn't entirely a good person. He has his moments of being completely horrible, like his reaction to the Family of Blood. He's often paralleled to the Master with a two sides of the same coin thing going on. So many players just focus on Ten's perky and energetic, let's go look at stuff whoo exploring! side but they never address the fact that he's kind of a jerk during a lot of his travels.
Finally, be ACTIVE. This goes true for any Doctor, but my biggest pet peeve is a Doctor that is inactive and just sits around while stuff is going on. Get him in plots! Do stuff! People will tell you if you think you're throwing yourself into too many plots, but actually have him DO something.
Re: The Tenth Doctor
And realize that Ten isn't entirely a good person. He has his moments of being completely horrible, like his reaction to the Family of Blood. He's often paralleled to the Master with a two sides of the same coin thing going on. So many players just focus on Ten's perky and energetic, let's go look at stuff whoo exploring! side but they never address the fact that he's kind of a jerk during a lot of his travels.
Finally, be ACTIVE. This goes true for any Doctor, but my biggest pet peeve is a Doctor that is inactive and just sits around while stuff is going on. Get him in plots! Do stuff! People will tell you if you think you're throwing yourself into too many plots, but actually have him DO something.