Regarding upgrades, I'll happily report about my experience (don't get worried about my low post number, I've just registered a few days ago to help someone with the new Curio in the South of France as I'm a very active member of the German Vielfliegertreff and just a regular reader here). I've been to Labriz in June last year with my girlfriend and sent an E-Mail prior to my arrival asking for an upgrade to the Hillside Pool Villas as we were looking for utmost privacy and a nice plunge pool. The request was noted and a day before our stay the upgrade was already visible in the app. So, asking as a Diamond member can definitely help.
Other than that, I can second the other comments here, particularly the review of Timo. I loved the a la carte breakfast in the Italian restaurant (Steak & Egg, ...), which was better than everything I had at any other Conrad (including the likes of Koh Samui, Hong Kong, Algarve, ...) and found the further benefits (complimentary bikes all day, massage to be quite nice). There are also a couple of complimentary activities including tennis, yoga (not all classes) and so on. Everything else is a little overpriced in my opinion, from the transfer to the hikes to the food, but I think that's what you get into when you are booking a villa on a rather private island. As noted above, the hotel doesn't feel "ultra luxurious", but very much down to earth and the location is just great.
I'll happily answer any questions if there are any
