You answer:

Dubai International is absolutely insane for this kind of trip. You could literally spend days there exploring all the shops, restaurants, and even sleeping pods. Singapore Changi is like a theme park with gardens, movie theaters, and a waterfall inside! Istanbul's new airport is massive and super modern with incredible architecture. Just make sure you book those long layovers during the day because some attractions close at night. Also check visa requirements because some countries let you explore the airport without a transit visa but others don't.