Yes refurbishment is really needed at HNL.
I have had many connections through HNL that were several hours in length so I have had significant experience airside there. There are parts of the Diamond Head Concourse that are very tired, although I love that there is still a Quizno's there. The UC there is among the best in the system so its a good place to hang out for any extended connection. UA is working on the Diamond Head Concourse, but as of early April they had only started some of the reframing on the second floor.
Aircraft spacing, baggage claim and overcrowded waiting areas need work. All of the extra seating in what used to be open concourses may be necessary, but its also old and in the way.