While I like that Sparity was left ambigious, I simply can’t believe that Rarity was totally ignorant to Spike’s physical change. I think that after all the pushing and pulling, back and forth, Like a Fine Wine scenario would be a lovely ending (given of course, that he didn’t end uo with Gabby, buy since I didn’t see her by Spike’s side, I am going with Rarity here). I think that Spike and Rarity may become a long distance relationship (with her presumably residing in Yakyakistan and him travelling around Equestria to mantain peace around the world). May be platonic, may be sexual. Although I like the idea that Gabby and Rarity switch Spike every year between them and Rarity shamlessly stares at Spike’s body when she was away for a long time.