A lot of epic vids and pics have been posted already, but I might as well answer the questions
My favorite thing(s) about her: She actually makes eye contact, as if looking straight into your soul. She hunts your smile. Furthermore, I like how she gets embarrassed really quick, but still manages to deliver awesome performances as an actress and as an performing idol. In addition, her voice is irresistible.
If you could change one thing about her, what would it be? Dislike of meat

On the other hand, lack of meat is what gives her her pale skin, which I absolutely adore.
What would you like to ask her? You are not in the group shot in front of the Eiffel Tower in Paris, what were you doing that day?
A picture and/or video that I like: Any. I'll just pick a random old and recent one:
How would your ideal date with her look? I can see myself having a dinner date with Rena. Just talking, having a good time. Afterwards maybe some karaoke and after a while falls asleep against me and I'll carry her home.