Generally the launch angle assigned to shafts is based on the design profile of the shaft and verified by testing. Of course it can and will vary from player to player depending on many things in their game. Basically it should be used a general guideline on what the trajectory might be produced from the shaft for any given player. Also, generally speaking, the higher the trajectory identifier, the softer the mid to lower section of the shafts will be. The softer the mid and lower sections of the shafts are, the softer the feel of the shaft should be.
You mentioned the Kuro Kage shafts played different than the Scores. They will, for several reasons, but no matter if the specs are identical between steel and graphite, they will always feel different. So when someone asks me what graphite will play like my steel shafts, I tell them there isn’t one. Yes, you can probably find one that produces similar ball flight results, but the feel will always be different. If you are looking for another graphite to try, I think the SteelFiber product, the Recoil product and the Rapport product we developed with VA Composites are all good products. Kuro Kage and the other MCA product is as well, but since you have tried those, you might consider these others.
Hope this helps.