The Watergarden is beautiful - we have stayed there twice. Candi Desa doesn't have much to offer - not even good restaurants. We only go there to stay at the Watergarden so if you are happy to lounge by the pool and eat in I would say go to Candi Desa. One idea is to travel there via the Watergardens (not the same place) and do another day trip around the coast to Amed - worth seeing the difference to the usual Bali, then a night at Watergarden
Dont stay at the Cahaya Dewata - its really run down and depressing with few guests - just go for lunch and you can sit in the restaurant looking at the view.
Klub Kokos is in a really pictureque quiet spot, staff lovely and pool excellent, rooms have seen better days but can't fault it for the price. Far out of town which is a nice walk in the daytime but you need to get taxis at night.