A key consideration in what you will be able to visit will be the flights that are available to connect the islands.
I have only been to Mauritius, Reunion, and Seychelles in 2022. Had originally planned to visit this area in 2020 including Madagascar, the Comoros, and Rodriguez island but Covid happened.
In 2022, I flew into Mauritius from Joburg. Spent 3 days enjoying the beach but also driving around the island soaking in some of the Culture (esp the Indian diaspora that makes up a chunk of the population). Also visited the national park but didn’t do any hiking- some good views but not jaw dropping.
I used Air Austral to get from Mauritius to Seychelles. Since all of their flights go through Reunion Is, I was able to get a full day there with a 24+ hours layover. Rented a car and drove around including into an extinct volcano. I’m used to mountain driving but this was really tough driving since the roads were so steep and curvy. Great scenery and there were lots of other areas to explore that I obviously wasn’t able to get to. Again no hiking since I didn’t have much time here. Note that Reunion is very popular with the French with at least a couple of large aircraft arriving daily from Paris.
Seychelles is more of a beach and honeymoon destination. I only stayed on Mahe since I didn’t have more time to visit a couple of other islands. Beautiful beaches, steep and twisty roads, interesting fauna and fauna but very pricey.
My recommendation would be Reunion though this will be another slice of France with great scenery and with areas where I believe you can snorkel. Hope this helps.
