It  sounds as if you are right on track for refinishing your Kaholo.  Every Spring I refinish my board.  I remove all the hardware, give it a light sanding and refinish it..  I use a random orbital sander non the flats with about 22o grit and hand sand the edges, shear and chine being careful not to cut through to the resin/glass.  I have not varnished any of my boards.  Instead I use a clear linear polyurethane.  I like  Awlgrip products.  Some of the Awlgrip products are three parts.  Awlgrip has a new product called AWLWOOD which is single part and perfectly clear.  You can put it over old cured varnish.  It is very durable.  check it out.  I apply with a foam brush.  Between coats I sand with a Scotch Brite pad.