This is probably the wrong forum for this post (I'll let the mods handle it), but i stayed at the Marriott Puerto Vallarta recently and was very impressed. they have an inclusive option and, for what you are looking for, the food was really above par (you have access to a japanese and seafood restaurant that are of decent quality) and the rooms were recently redone. Also, while being a chain, it doesn't have that chain feel. By no means is it a truly upscale resort, but it was really nice. I used points to stay there and then upgraded to a very nice suite (about 1000 sq ft inside and another 800 sq ft outside) for only like $200 a night more. Its close to downtown, where you can experience night life, but its on the other side of the marina, so its a bit more "secluded". When i was there, there were literally no kids around (only couples and people on business), so you won't get that family resort feel. We also took a private yacht out on the bay at sunset and it was a very romantic and enjoyable experience. They also redid their spa and i actually found it of very high quality with many relaxation rooms (i think there were like 6 different soaking tubs of different varieties) and a large list of services (again, not "luxury" but much nicer than other chain resorts i've been to).

sorry to say, but you won't be getting One and Only for $4500 all in. While this isn't "luxury" its still a very nice option for your budget.