Just like " Lia and Lara will seek the One Piece " and " One Piece Messenger of the sea " RRL OR NU are fine ^^
"this bites" at fanfiction.net, is practically the only good one piece fanficton I could find, and have you ever thought about going on this site or Wattpad and search in the one piece section? admittedly 99% are bad, but if you search enough I'm sure you can find a hidden gem.
Well it's NU.. but I gotta warn you that the story plot is following another character and not the straw hats. I'm currently reading the raws (221 atm) and I'm enjoying it.