There were awesome little moments in the episode. It was Rachel-heavy, which was not awesome for me, and I just kept reminding myself that Rachel is supposed to be annoying. The reprise of "Don't Stop Believing" was cool in that it had the original six New Directions members, even if five were in Rachel's imagination.
The Finn and Puck parts were mixed for me. I'm not a big fan of Finn as a character. Callie contributed to putting me off him, though I'd realized that he wasn't as nice as he liked to think he was. However, I was thinking of real life, of the actor missing the last couple episodes of the season, and wishing him well.
Unique was taking birth control pills. Marley told her not to, but I was somewhere between shock and delight that Unique was taking hormones. It's not safe to take them illegally, and Unique couldn't legally get estrogen at her age without her parents' approval, which she certainly wouldn't get. But I loved that Unique was so determined and impressed by the research she must have done. (Edited to add: And Unique said "trans kids," including herself in that.)
Marley's original songs came up, and one of the things Kitty said was that people didn't want to hear "a song about loving an octoroon." I recently did a post on outdated racial terms, and that was one of the words I wrote about. From my understanding, it's okay if someone uses that about themselves, but it's offensive otherwise. It was Kitty, though, so I figured viewers would realize she was being offensive. Jake did get a reaction expression.
Blaine started to think Becky was covering something up about the shooting. I think that will get followed up on. Coach Roz Washington took over for Sue, and she was offensive, too. She was really offensive to Becky. She called Blaine fruity. When Blaine asked Becky if she knew something, Becky said, "Mind your own gay business, Gay Blaine!" She knocked over a xylophone, too, harking back to when she was upset about not getting the votes to be nominated for prom queen. Becky was using "gay" as a slur, and Blaine must have known it. That's another one where it depends how someone's using it, but is usually used neutrally with Blaine. Blaine doesn't get slurs from New Directions, but he's getting them from Sue and Roz and Becky.
McKinley had its share of interesting bits about race and gender and sexual orientation this episode.