Ranking the Princess Episodes (From Worst to Best), Version 2 · 1:36pm Sep 30th, 2019
Well this updated list is going to be a little bit different, owing in large part to the fact that Cadence hasn't gotten anymore episodes dedicated to herself, and Celestia and Luna have only had episodes where they share the spotlight. There really wouldn't be a point in talking twice about the exact same episodes for both characters, especially when they end up in the same spot. So I'm just going to list all the episodes focused on the princesses based on how I feel they function as focus episodes for them, then after that I'll explain why the new episodes got added where they did. With four more episodes to consider the total number of episodes focused on one or more of the princesses has been bumped up to 17. Here's the first version, from March.
17. Princess Twilight Sparkle Part 2 (Season 4, Episode 2)
16. Do Princesses Dream of Magic Sheep? (Season 5, Episode 13)
15. Three's A Crowd (Season 4, Episode 11)
14. Bloom and Gloom (Season 5, Episode 4)
13. Luna Eclipsed (Season 2, Episode 4)
12. and 11. The Beginning of The End Parts 1 and 2 (Season 9, Episodes 1 and 2)
10. A Royal Problem (Season 7, Episode 10)
9. Between Dark and Dawn (Season 9, Episode 13)
8. Once Upon a Zeppelin (Season 7, Episode 21 in production order/22 in airdate)
7. Celestial Advice (Season 7, Episode 1)
6. Sparkle's Seven (Season 9, Episode 4)
5. and 4. A Canterlot Wedding Parts 1 and 2 (Season 2, Episodes 25 and 26)
3. Sleepless in Ponyville (Season 3, Episode 6)
2. For Whom The Sweetie Belle Toils (Season 4, Episode 20 in production order/19 in airdate)
1. Horse Play (Season 8, Episode 7)
Now, as for why the new episodes landed where they did: "The Beginning of The End" did lampshade how the princesses have never really helped against any of the big threats, but I don't like the attempted handwave that it was all intentional, a test to groom Twilight to take over. That is an incredibly reckless and irresponsible thing for them to do, to say nothing of them forcing their retirement onto Twilight even when it's obvious she isn't prepared to take over so soon. They do learn their lesson in the end but it's still quite jarring to see them make such a mistake, Celestia especially considering she's seen what can happen when Twilight gets all worked up. "Between Dark and Dawn" does focus on the royal sisters, but it's weighed down by them once again arguing as if that's all the show can think to do with them in the spotlight. Thankfully, unlike "A Royal Problem" where they were basically forced to realize their mistakes this time around they actually learn on their own and make amends without anyone else compelling them to do so. As for "Sparkle's Seven" even if it wasn't the focus there was still the sibling rivalry between Celestia and Luna, with Luna not being trusting of the new castle security. It's understandable this time why Celestia doesn't acknowledge her sister, because Luna has been keeping her frustrations to herself. But it's clever to see Luna work with Spike to sabotage the security system and thwart Twilight's plan, and it proves a valid point: The best security system means nothing if you've got a threat on the inside that knows how to get around it or defeat it. And in case you're wondering, I don't count "The Summer Sun Setback" as a princess episode since the royal sisters are largely witnesses to Twilight's character growth here, though more so than other episodes this season it felt like this was a good send off for them and a way for them to pass the torch (one last Summer Sun Celebration, which Twilight then replaces with a holiday dedicated to them).
And there you have it.