This episode feels like an epilogue to Ash’s adventures in the Indigo league. The next episode references the league, but it doesn’t tie up any loose ends; it just introduces the next adventure.
Team Rocket didn’t need to appear, but without them the episode would’ve been too short to broadcast. I suppose they could’ve made Ritchie’s battle longer, but he wasn’t the main character; what we saw was probably more than what was needed for the story, & seeing Ash & his new friend work together was fun.
I like the closing ceremony, tho the fireworks aren’t as impressive as I remember. All in all, I’d say this is a fitting conclusion to the Indigo Saga, with a decent call to further adventures.