RE: Severne Sails & North Masts
Your NS mast should be all right for the Severne Sails (NCX, Gator or S-2)
The 3 ranges will all work good for what you want (Blasting, jumping and freestyle)
The S-2 is probably leaning most towards jumping and freestyle and the NCX is excellent for blasting/ speed. The Gator is close to the NCX in performance, but with a softer feel
For your specific size that you are after (6.5) and Kombat 96 I would recommend the S-2 6.4, especially if your progress towards more jumping and freestyle.