I found on my 1st trip 5 days was ample in BKK. Now when I go it might just be for a few days at the start or end of my trip.
Hotels... Majestic Suites is a great little hotel around the corner from Nana Plaza. Many BM's stay here and it is a very popular hotel. Although they have not got there own pool or spa you can use the Majestic Grande's facilities, which is about a 5 minute walk away.
Majestic Suites Hotel, Sukhumvit Nana in Bangkok, accommodation hotels Bangkok.
Bangkok Five Stars Hotel Thailand, Discount Budget Hotel and Hotel Booking At Majestic Grande