I've done 3 all inclusives in my life.
Punta Cana (Iberostar), Negril (Beaches), and Lucea (Grand Palladium)
All we're great, yet different. The Negril one was by far the best because the resort was more higher end compared to the other two and way more expensive. Also, Jamaican people are just awesome.
Food is a big factor for me. The food the 2nd time in Jamaica (Grand Palladium Resort) was fucking trash. The resort itself was amazing though. Just do your research and read lots of reviews. You get what you pay for.
Punta Cana, I was 16, so I was just happy my parents allowed me to drink. It was a great trip, we did a crazy open air bus trip.
5 days is perfect and 4k would definitely get you some lavish accommodations. I've seen decent ones going for $1200/person.
If I was interested in another, I'd check out Puerta Vallarta. I've heard great things.