It's your money and ultimately your happiness with the results either way you go. I don't ski at your level , but at the end of the day a1994 Mastercraft prostar is a 1994 prostar regardless of the upgrade. If you try and sell it down the line a very small percentage of buyers will understand the upgrade therefore you will never get any return on it. I appreciate people say this is the last boat I will ever own ,I've said it myself , but a new cooler boat comes along and who knows you may want it. A 2008+ nautique will not only give you the ZO pull , but give you more room with a trunk , better tracking , and a better wake. Not to mention a boat that will give you a better resale if and when the time comes. If it were me and I could do the mechanics like you , fix the current motor , sell it for 10gs amd buy a Nautique ! You won't regret the decision now or later.