About time I posted here...I like when:

-People get the right amount of detail, i.e. are not too descriptive and not too sketchy. When I read a post containing 3 lines or less, it's impossible to respond to it, but excessively long posts are equally bad because I get too distracted or bored to read them to the end.

-The RPer uses correct grammar and punctuation. Mistakes discourage me from reading any further.

-There is a clear distinction between speech and thoughts. I like it when spoken lines are bolded, so that I know what my character should respond to, without risking to come across as a mind-reader.

-The RPer puts a lot of thought in the character's background and is creative,whilst avoiding to tamper with the canon Potter-storyline.

-People leave open endings so that everyone could reply if they wish.