Where you stay in Bangkok comes down to one question: do you want the BTS or the river?
Most first-timers pick a Bangkok hotel off a map and don't realize the city splits into two categories: neighborhoods on the BTS/MRT lines, and neighborhoods that aren't. That's the actual decision, more than any "best area" list.
Riverside and the old city (Grand Palace, Wat Pho, Wat Arun) have zero rail coverage. You're on river boats and Grab the whole stay, which is atmospheric but slower than people expect. Sukhumvit is the international strip, on the BTS the whole way, hotels at every price point, and honestly a bit generic. Silom and Sathorn get you both lines plus Lumphini Park and feel calmer in the evenings. Ari is where I'd point someone who's been to Bangkok before and wants a normal neighborhood with good coffee instead of a tourist zone.
Two airports matter too. Suvarnabhumi handles most full-service flights, Don Mueang is the low-cost carrier hub, both are 30-60 minutes out depending on traffic. Weather-wise, November through February is as good as Bangkok gets: lower humidity, actually walkable in the afternoon.
I put the full breakdown together with the neighborhood map and the airport comparison at thai-travel-guide.com/destinations/bangkok if it helps with planning. Happy to answer questions on specific areas.
