Bangkok
The best street food on the planet, and a transport system that makes the chaos navigable.
Three or four completely different trips sharing one island.
Bali gets flattened into a single image, but Canggu, Ubud, Uluwatu and the east are barely the same holiday. Surf-and-cafés, rice-terrace-and-temples, clifftop-and-sunset, and quiet-volcano-village all exist here, and picking the wrong base is the most common way to have a mediocre time.
Split your stay across two areas rather than day-tripping everywhere from one. Traffic between the south and Ubud is bad and getting worse, and an hour on a map often means two and a half in reality.
Dry season without the July–August peak. Consistent surf, open roads, and prices below high season.
A workable shape rather than a schedule to obey — two fixed things a day, and room to change your mind.
Grab and Gojek work in most areas but are restricted near some beaches and markets. For anything beyond your neighbourhood, hire a driver by the day — it's cheap and much less stressful than a scooter you're not confident on.
Villas with a pool are the reason groups love Bali: splitting a four-bedroom villa costs less per head than hostels elsewhere. Decide the villa-versus-mobility trade-off early, because the nicest villas are the furthest from everything.