If it's Toucan, then there's some plan to re-develop KonTiki. I've seen artists renderings somewhere of what it
will look like.
I'd look farther West since the diving is better. Habitat Curacao, Sunset Waters or Lodge Kura Hulanda. Of the three you'll find that the best diving is at Kura Hulanda in West Punt - Playa Kalki and Alice in Wonderland, followed by Habitat then Sunset Waters. We dove all three and I'd rate them in that order. Best boat dive is Watamula west of Kura Hulanda. Most of the diveops, even ones in the city go there weekly.
Rent a car if you're considering any of them, otherwise you're mostly stuck there. KH is 45min. to an hr. from town, Habitat and Sunset are in pretty remote locations. They all have shuttles to town but what a pita. Especially since there's such great shorediving all over the island.
Unless you want to be nearer to town, then look at either Lions Dive, Breezes or the Marriott. I wasn't too impressed with the reef off Lions Dive either, at least where we went for the Dolphin dive, it was pretty barren. But it may be better to the west.
Ocean Encounters is the largest dive operation on Curacao. They own/run the facilities at Lions Dive, Toucan/Kontiki, Breezes and Kura Hulanda. I had a good overall experience with them at both Lions Dive and Kura Hulanda.
Edit: I agree with what DF posted below, Habitat looked a little tired last April. Sunset Waters looked worse. Depends what you're looking for. Of the two, I'd pick Habitat, at least the diving is better.