Many people buy dirt cheap high wind sails to save money and the fact they will not use them often. That is a mistake and will ruin a high wind days sailing.
The Neil Pryde Core is a very old sail that was Josh Stone’s signature sail. It had four battens and was designed specifically for light weight freestyle sailors and light weight wave sailors. It is totally unsuitable for a heavy weight on a 120 litre board in bump and jump conditions.
The board and fin is fine for now.
Buy an Alpha 5.4 as soon as possible if you want to sail well in 30 knot winds. The difference will be unbelievable.