I'll be more in depth later on (be it on this thread, or in a PM) but I think the biggest thing you can do to improve yourself is be versatile. Don't get yourself stuck in a too linear story, or an overly similar approach. The biggest thing I can think to help with that would be giving the character a personality disorder of sorts. For everyone feeling this way, I urge you to take this test in character:

http://www.4degreez.com/misc/personality...er_test.mv

Learning of what disorders they may suffer from lets you know how to put that into an RP. For example, if the character scores high or very high on antisocial, and they injure or kill someone in the story, have them show no remorse.

That in turn adds depth to the character.

Remember; even if you aren't the best writer in the world (not saying that anyone is a bad writer by any stretch of the imagination) if you can get the people reading it to be interested in the character, they're going to keep reading your work as you improve.

Also, I've said it before and I'll say it again. Write like a reader. When reading other people's RPs, or books or whatever it is you read, what are things that are in them that you like? I know I like internal struggle, and despite not knowing a whole formal lot of the subject, psychology. That's what gives me the inspiration to write as Jessie.

For Luca? Yeah, I like crime drama. Again, internal struggle. Humor. I use that a lot when I write Luca, and it seems to click.

So yeah, write like a reader, man.

Wow, this was a lot more in depth than I expected it to be.