I would take a look at Aruba or Barbados. We are a group in our mid to late 20’s and had similar vacation requirements as you. We chose Barbados based upon those requirements. Aruba would have been fine as well, but we wanted an island with more of a Caribbean flair.

For Barbados, I would look at the St. Lawrence Gap area if you want to be close to nightlife. There are some pretty luxurious resorts in Barbados as well, but expect to pay top dollar.
You can find villas and vacation rentals (for any destination) at the following websites:

www.homeaway.com
www.vrbo.com
www.airbnb.com

www.homeaway.com
www.vrbo.com
www.airbnb.com

Ooops! I see that you have already been to Aruba, sorry! Do look into Barbados though. Negril, Jamaica may also be an option.

i too think barbados will be a good choice. most villas there come with staff & a better price by the week so maybe you can skip the resort move. are you going to rent a car? nicer beaches are closer to speightstown (gibbs, paynes, mullins, reeds)
friends stay at bougainvillearesort.com every year. it is very close to the gap.

another option would be a condo on seven mile beach on grand cayman. very safe island.

I love Negril but "villas" and "pampering" don't really come to mind.

Jamaica also doesn't have much nightlife except what is provided at the resort. I agree with the recommendations of Barbados.

There aren't any villas on the 7 mile beach in Negril but there are villas in the area. They are however, $$$. Friends stayed at one a few years ago and loved it. They had their own cooks/maids / private beach etc.

I think Barbados would be a better option though.

Check out Tortola. Nice beaches, some beach bars/night life in the Cane Garden Bay area, good side trips to other islands and the Willy T.