Ten days structured to balance sightseeing, food exploration, day trips and genuine rest.
Grand Palace and temples; Chinatown food evening; cooking class; Canal tour on Day 3.
Sukhumvit and Thonglor; Chatuchak weekend market (Day 5 if Saturday or Sunday).
Ayutthaya for history or Amphawa for the floating market — full day.
Dusit and Bang Krachao cycling; MOCA and Silpakorn galleries.
Day trip to Koh Chang or Pattaya for a beach break.
Morning market; massage; final neighbourhood; packed dinner at a destination restaurant.
Ten days is enough to add one full day trip and still feel unrushed — resist stacking two major sights in one morning, since heat and traffic eat time faster than the map suggests.
Swap the beach day (Day 9) for a second slow day in Bangkok if flights or ferries make Koh Chang or Pattaya inconvenient — the itinerary holds together fine as a pure Bangkok-and-day-trips trip.