I am not sure what you sell, however, I was selling prom dresses mostly at one time. Unconditional returns meant buyers assumed they could wear and return after prom. (altered, dirty, etc.) So I put 3 days, but do give leeway mainly depending on if they just say size does not work, or if they make something up that I know to be untrue. That gives buyer time to try on and see if it fits. But not to wear to their event usually. I do not refund any shipping costs (unless item is defective when returned) however, those that want their shipping costs back, just go through ebay and they refund original amount with shipping. (so buyer only has to pay one way shipping) Now I rarely have issues on formals, I can't remember last formal that one even asked for return on.
I frankly do not buy based on sellers return policy for two reasons, no matter what that "policy" I know "real policy" and only use if item is trash when I receive it and totally not as described. However, I do not restrict my purchases to sellers who will take returns, as they are usually selling cheaper than those who do) I am not going to pay return shipping on anyway. My real policy on buying is "can I sell it if it does not work (size, color, etc.) for what I paid for it? If not and I am not 100% sure of size I do not buy. Most of the time I have found I can make money on items I am not happy with which has been added bonus.
As far as feedback, I have found that basically unless I offer FULL REFUND, (including shipping BOTH ways) period they may (or may not) leave decent feedback but low star rating in every area that is not always true.