It's an okay yet lackluster show. This was the first season I watched while it was airing since its premiere. Tropical-Rouge can be described as having an interesting concept but executed poorly.
For a show that is supposed to be about mermaids (one of my favorite things ever), the sea, and makeup, it sure focuses more on school and club activities a lot. The fight scenes were also really disappointing, they make the Cures look weaker. The character development was severely unbalanced with some of the main cast having more of a presence in the story (Laura/Cure La Mer and Manatsu/Cure Summer) and other that are more just... there. *cough* Sango/Cure Coral *cough*
On the positive side, I really liked the transformations and art style. The comedy and color design are nice as well, and I also liked the interactions in the cast, which made the show more enjoyable. And Asuka/Cure Flamingo is my favorite Tropical-Rouge Cure, if not one of my favorite Cures of all time.
Unfortunately, when talking about Tropical-Rouge as a whole, I had more moments of me being disappointed than enthusiastic while it was still airing. I'd recommend this show to someone who likes comedy or anything that doesn't take itself too seriously, but I'll say this: expect a lot of disappointment if you prefer to focus on the lore/story.
Overall rating: 7/10 (it's my least favorite PreCure season, I'm sorry about my ramblings)