For a luxurious stay in Bangkok, I recommend the Mode Sathorn Hotel. Besides the comfortable beds and the charming room, the bathroom was very impressive. It had a ceiling mount rain head shower and a full window right next to the bathtub. Bubble baths to the day and night view of Bangkok? Yes, please.
There is also an infinity pool in this hotel and a rooftop bar that are all instagram-worthy. I suggest trying the Thai-style cocktails the bar offers- the Tom Yum cocktail was very interesting in flavors.