Getting between Mykonos and Santorini is a long transit. I would stick with one island with only 4 days. Choosing an island is largely down to personal preference. Mykonos is often described as a party island, but we non-partiers were there in the shoulder season (October) and loved it!
The vast majority of those people live in Santorini (the main island), and about a few hundred on Thirassia. So, slightly over 15,000 people live on Santorini. These are permanent, year-round residents. Most of the residents live inland or on the beach side of the island. There are permanent residents in the cliffside towns of Firá, Oia Santorini will be very quiet & lots of places close down as of Nov 1 - reopen around easter. Still can do long walks but will be quiet. Also to reinforce that 'off-season' means something much different than it does in a lot of holiday spots. Traveling to Greece early October with a group, splitting our days up in Mykonos and Santorini. For Mykonos, we are debating whether we should stay in the downtown area. Is it worth it during this time of year? We’re not sure if things will start shutting down while we’re there given it’s the shoulder season. As someone who displays the game out of the box, the ocean board is essential to its presentation. With the expansion included, I really only paid $10 more because I did the group buy to get the price down. Also, if people who get the Target version go out and get the expansion, the cuts of the cards are different.October is an ideal time to visit Santorini. Many seasonal flights and restaurants finish for the year this month which means that, despite it being shoulder season, the crowds that filled Santorini over recent months are gone.
Fair enough. My Reddit opinion is that the game isn't worth it unless you really like the theme. Part of the allure/hype of it is that it's heavily hyped by the BoardGameCo and Quackalope crews -- these folks are boardgame marketers, not boardgame reviewers. I've long since learned to stay well away from games they lean into endorsing. .