Joe, a few clarifications.
Is the 15k for all 18 days including diving and accommodation? When you say unlimited house diving, do you mean included in the price? Or just that they won't stop you from going for that 9th dive at midnight?
Which criteria is most important? Can you list it in order of preference.
Many of the resorts in the Maldives/Tahiti with overwater bungalows are pretty big in size and most certainly aren't the dive till you drop type places. The house reefs are more snorkel depth which graduate to walls. The best diving are channels with drifts done by boats. Check Euro Divers or Werner Lay dives for their sites as they run a few concessions at various resorts. I remember one Euro Divers resort Viledu (or something like that) that had a house reef that survived the bleaching during the worst El Nino years.
I can't think of a small, service oriented (luxury?) place that has a good house reef with unlimited(number wise) EAN diving except the following places:
Indo: KBR, Lembeh Resort in the Lembeh area. Not small but hey it's much heaven.
Bali: Scuba Seraya, Villa Markisa, all of these resorts charge per dive but it's like $30 or something. Mimpi Tulamben has unlimited air diving in their packages usually. But that's like on the row of hotels/resorts on Tulamben beach.
Ambon area: Maluku Divers in Ambon (muck), Cape Paperu resort in Saparua (sandy/coral reef). Never stayed at either but have dived the areas more than a few times and know the people running the place. Decent small places but not luxury.
There are a few off the beaten track resorts with house reefs like Wudong (muck), Alor (shallow reef), Banda Neira (junk muck), All of these places will let you dive without a guide and no EAN, if you have the experience.
Then there are places like Central Sulawesi like the Togians and other resorts in the area like Gorontalo which are pretty decent for critter.coral dives but lacking in bigger fish (fished out). All small but 3.5* at the most in Togians.
For luxury but not unlimited shore diving, very private with a decent house reef, I can think of the Aman Wana resort in Moyo. I can't remember if they had EAN. Taking the seaplane from Bali will bust your budget so it's a bitch to get out there by boat.
Anilao has the best shore diving depending on resort but no beaches and the food is decent at best. The areas of Moalboa, Sequijor and especially Sogod have decent smallish resorts that have good house reefs with EAN diving and great beaches.
I suggest you check Theresa Zubi's website for areas and get your priorities listed with deal breakers and specifically level of accommodations (must be luxury, simple etc)