Rider vs Alter was one of the best fights I've seen in a while. I cannot say I understood everything that happened, I had Reddit open the whole time cause I kept needing to pause and look for explanations for lore that's glossed over or only vaguely explained. I felt Kirie's presence was not all that important. I also felt that Ilya shouldn't have sacrificed herself, it makes what Shirou was doing feel less important.
In the end, I still prefer Rin