i had planned not to respond, as i don't really like to deter people and i love a good project as much as anyone else in this forum
but when i read your post, i thought to myself "Why, why, why?!?!"
the reason for that is rather simple---i think you are giving yourself unnecessary work/expenses in this day and age. If you had this idea 10/20 years ago i would have endorsed it completely as back then we did not have the plethora of forged parts readily available on the market like we have now and people had to be ingenious to save money and/or create suitable parts for their builds/projects. We seldom have to do this today, unless the person is really going for something extreme. In the meantime, you can maximize the stock engine with a good tune and set up and maybe achieve or get very close to your current goals (200whp). After this point, i would suggest you invest in some forged pistons and rods to get to the next level you mentioned (250/300whp), as even the cheaper forged options should get you there. For all the research and additional works that you plan to do to run NZ or any other oem pistons, rods, gideon pins, rings, whatever, you might as well get specifically designed 4e/5e forged stuff and do it properly and know exactly what you are dealing with upfront---no guess work. And yes, initially, i know it may sound cheaper to use "NZ pistons and other oem parts", but are the savings (if any), even worth it and the hassle. I'd also suggest that you set up a spreadsheet and look closely at the cost of both alternatives to help you with your decision. When you determine your project budget, if you don't have all the funds, then save towards it.
all the best whatever you decide