My top 5
1) Get rid of the hot and heavy pigs and go for 2 into 1.
2) Black Dog skid plate...'nuff said!
3) Seat Concepts tall seat (or Renazco, or....)
4) Gotta have power (under the tank plug)
5) Oil change relocation
Too many other things it needs like suspension work, new tubeless wheels, steering stabilizer, and better lighting; among other things. Oh, and don't forget to at least add some fuel capacity for any long journey.