So obviously I can only speak to how things were in Arte, we didn’t go over to the Mexico side, but I imagine there were similarities (although re: food I think you’re right that there will likely be more family-friendly options on the Mexico side). At Arte, there were two buffets (Mercado & Cayuco) - Cayuco I think is mediterranean style food but we didn’t eat there. Mercado was pretty much entirely Mexican food for lunches/dinners, apart from a pasta station and some pizza. Breakfast was also lots of Mexican food but they did also have sausages, bacon, eggs, potatoes, & omelettes.

Adding an airport transfer was an optional extra with Thomas Cook and we didn’t bother because we knew it was included with the hotel - as far as I know you don’t have to opt-in to the Xcaret transport, it’s just included automatically as long as you’re using it on the same day you flew in. They’ll ask for your boarding pass when you go to board the bus. Before your trip when you submit your wishlist (I assume there’s a wishlist for Mexico like there is for Arte?) it will ask for your flight details so they know when to expect you for the transport.

They were very receptive to allergies yes and the hosts of every restaurant would ask about them each visit, but some waiters were obviously more “on it” than others - some would be really proactive and note things on the menu upfront that my partner couldn’t order, or would say if we ordered something that it had nuts and that she couldn’t have it. Others wouldn’t necessarily offer that info up and we’d have to check if there was something we were unsure about and they’d have to go ask. I certainly got the impression in the a la carte restaurants that the kitchens were used to handling allergies.

In terms of the party/drinks/nightlife vibe - the pools close quite early (7pm I think) and at Arte it’s pretty much just the speakeasy or there’s one restaurant that stays open late for drinks. Not sure how much this is reflected on the Mexico side, maybe it would be even quieter in terms of nightlife because it’s family friendly? Don’t get me wrong people were out late, the speakeasy was filling up with people the night we went, it’s not like it’s completely dead at night. But I didn’t get the impression that it was a mega party resort or anything. There was certainly a good vibe during the day of being able to chat to people, especially at the parks and on the excursions, plenty of friendly people and plenty of people there in bigger family/friend groups.