A lot of my customers ask me whereabouts to stay on the island. When I visited the North I stayed in 4 hotels in one week (Iberostar,Gran Ventana, Riu Merengue, Victoria resort) as I was on a work trip. I also visited several others. Although the hotels are as good in the north as they are in south, the beaches are not! In the north the ocean is the Atlantic so the sea is not clear and not very warm. In the south the beaches are on the Caribbean ocean so the sea is much clearer and warmer and also much better for scuba diving.
I stayed at the Sirenis Cocotal hotel which is part of also the Sirenis Suites hotel. I stayed here for a week it was a very good standard of hotel and budget wise very affordable. There are often many different offers for the 5* hotels so depending on when you are travelling I will be able to advise you who has the best rates at that time.
Punta Cana is also very close to Bavaro which is very similar and on fantastic beaches. As good as anywhere in the Caribbean I would say. There are choices of many different excursions from the hotels bookable on arrival. Most of the hotels are quite secluded so walking outside of your resort is not really an option, but you can still take the excursions from your chosen hotel.
Some of my top recommendations on hotels would be the Secrets chain (adults only) Bahia Principe, Sirenis Cocotal or maybe the Dreams or Iberostar resorts which would appeal more for families.
Overall a fantastic holiday destination that I would go back to and with a flying time of only around 8 and a half hours which is one of the shortest Caribbean flying times.