first, Thank you for writing a fic for me!
Now to get to the point why you are even here:
Since you have read the prompts you know I like to read a wide variety of things.
My favorite character is Dean but I also enjoy a well written Sam-centric fic, recurring characters, minor characters or outsider POV fics.
All in all, it's very easy to make me happy.
The only things I don't like at all are OCC behaviour (without understandable explanation) or losing yourself in details that are, after reading the fic completely, in no way relevant to the actual plot (I actually read a story once where the author described the outfit of everybody involved in detail for every new day of this fic, and No, neither the fandom nor the plot had anything to do with fashion!).
I'm looking forward what prompt you pick and what you do with it. :)