ikw777 said..
30% carbon is probably ok for those small sails - no need to change, you're set there.
A mast extender is just a lash-up.
For new sails you should just get the right mast/s. If something is worth doing etc....
Guy Cribb picked my 4.2m + 78ltre board for an on the beach rig practise demo.. he stayed at it for a few mins and then said 'this is too heavy " and went off and picked a lighter one..