Insomniac:
I spent two full days with a trained guide and a car and I felt good about how much ground I covered at Angkor.Over a dozen of the most famous sites,long lunch breaks,hundreds of pictures and I never felt rushed.
When I was researching the trip,a lot of people on the net insisted on 5 days minimum,but a lot also said after 5 days they were "templed out"
My honest feeling is that you can properly appreciate Angkor in 2 well planned days,but if you've got the time,and temples are really "your thing",take the 5 days and you wont regret it.
Just for fun here's my version,rushed but do able:
Nov 5-9 bangkok (get your feet wet,see some sights)
nov9-11 Sien Reap
Nov 11-17 Phuket (relax for a week,meet some BM's)
Nov 17-20 Pattaya OR Chiang Mai (do you want traditional Thailand and outdoor adventure or the largest collection of Go gos,beer bars and availabale women in Thailand?Your choice)
Nov 20-22 Use Hong Kong as your stop over on the way home and spend a couple of days there to end your holiday.

rushed but doable