Depends heavily on the genre. I prefer to use First person, as i can give more emphasis to the mind of the protagonist, but third person has it's advantages. At the end, both POVs got their pros and cons. There is no objective better POV.
Man, need to do it too sometimes, i went inside one once but never got anything. Seeing and realizing that you can buy 5 books at the price of one really fills you with joy.
Depends on the context, really. If it's for plot reasons, then i can stand for it. But if it's just to please the author's fantasies it does get weird.
I have been wondering, how does horror perform in this platform?
I'm currently writing an horror novel. It's still in my native language but i plan soon on translating it.