For leisurely dining, with a touch of elegance and serving unique, tasty and well-prepared food:
La Costera, Orchidee, Simply Red, La Roca, Bailey's, La Finca, Water Front, Terra Linda (in no particular order).
For consistently good food offering reliable service and moderate prices, with comfortable and friendly atmospheres:
Brittania, Rockys, Romanoff, Good News, BJ's, Hostaria (also in no particular order)
Obviously, Cubano Cafe is a great place for cafe, desserts, and quick sandwiches, also moderately prices, with a wonderful view of the 'happenings' across Pedro Clisante.
And these are just the ones within easy walking distance in the "downtown" area.
Sosua has a large selection of interesting restaurants, and sometimes the owners and the menus change, offering even more options. Sometimes it's nice just to explore and try something new for a change.