If you want to see kep hire a bike from kampot and ride there and take a day trip. The crab market is turned into a yuppy stalls selling other than that not much else. Kampot is full of pompous stoners but the evening river boat cruise up the river is good and ride a bike to Bokor and you can see phu quok elevation is 1200
MTR I think. 4 days in kampot would be plenty first trip.
As for kampong saom I have a lot of friends there I like to stay on Tola st 1 back from the beach road where the boat jetty is. From what I hear there are a lot of tranies blokes in a blouse on the beach once the resturuants side closes so drugging and mugging are the norm like coconut bar pattaya.