I like the suites in the intercontinental which are rather affordable if you are ambassador. In terms of expectations, while I always enjoy Bangkok, I am not sure there is a huge dating scene for a foreigner (last time I went as a single was 10 years ago when I was 25 so I cannot really tell). I do remember KL as being more of a dating place despite the muslim "thing".
As a whole BKK is great.
Re Meridiem, I would not want to stay in Silom. BT is in a good area and I would defo visit Babylon (at least one it should be experienced).