Ok,
There isn't anything in those numbers to indicate a problem that would discolor the plaster. I would like seeing some pictures, and understand what you mean by the "leaching" you mentioned. If that's just the discoloration, it happened during install. Not after the pool was filled, and it's called streaking or mottling. Without knowing more, and assuming those have been pretty typical numbers since filling, I'm not ready to place any blame on the chemistry. At all. Again, most appearance issues are by far caused by the installer/install quality. They often blame the chemistry, and it is hardly, if ever ever the reason.
Aside from the finish, those numbers are about to lead you into trouble with Algae. I wouldn't be advising you well if I didn't suggest you getting a good test kit, start learning about pool chemistry and addressing those numbers. Your Cya needs to start increasing soon, the FC needs to come up now, and the pH will soon be out of range to the high side. Forget about the phosphate number.
Start with the ABCs in pool school for a look at the essential basics. The link is above at the top of the forum, as well as the pool school links in my signature.