I've been to the Iberostar Dominicus in La Romana, as well as 2 other Iberostar hotels in Punta Cana & Puerto Plata, they are always lovely. More food than you can experience, lovely pool, great rooms with good maid service & fun entertainment. The beach there is fabulous & as Matilda mentioned it's close to Bayahibe which is a nice town to visit if you want a day out. I enjoyed Punta Cana but this area is super built up for tourism and is literally like a mega-complex of hotels in a row which isn't really my style. But again beautiful beaches and the hotels there are very nice. Puerta Plata was lovely as well and is located in a large city so you have more access to urban experiences if that is what you're looking for. But if I had my choice I'd visit La Romana again.
I'm currently on the south coast and it's lovely here as well (how many times have I said 'lovely'?), the water is certainly rougher and a bit less of that pristine, aqua blue color you associate with the carribean. But I certainly am happy with my choice to locate down here on the south coast, because, well it's LOVELY here
have fun, d