Bangkok (2 nights): Late arrival in the evening. We were only able to visit Wat Po. The rest of the time was spent shopping, eating, and eating
Koh Tao (3 nights): departure by night bus and boat from Bangkok, the trip lasts 11 hours. We took advantage of Tanote Bay (which we don’t recommend), Chalok Baan Kao (amazing!) And a boat tour of the island for snorkeling (and visiting Nangyuan, among others)
Koh Phangan (3 nights): departure from Koh Tao by boat, the trip takes 2-3 hours. We stayed at the Haad Son Resort (Booking link, best beach on the island), rented a scooter on the last day to get to the city center, and tour the beaches (including Chaloklum which we recommend for the beauty but who is infested with sand fleas)
Kabri (5 nights): departure from Koh Phangan by boat and bus. The trip lasts 5h30. We must have stayed here for a long time because I got sick. But if I was not sick, I would have visited Koh Phi Phi during the day, 4 islands -> 3 nights here and 2 nights in Koh Lanta would have been ideal
Bangkok (2 nights): flight from Krabi to Bangkok
Note: we skipped Chiang Mai, Chiang Rai, and Pai on our 1st trip. And after visiting them on our 2nd trip, I think you can actually skip them if you’re short on time (although I have a little crush on Pai). However, it can be an interesting stop if you want to go by boat afterward to Luang Prabang.