Welcome to Isshu, where everything is new and different! OH LOOK HOT SPRINGS.
By the way, I don't think Meguroko will be returning. If it does, great, but the little bit at the end is just something they always do (for anyone thinking it means anything). The glasses just helped differentiate it from the others and pinpoint it as the "leader" for the episode.
The best parts have Mijumaru. It's name definitely lends itself to a cute way of talking ("Mee jooooo"). I want more of this Pokemon. It even floats in the water like the early art renditions depict it, just like a real otter!