Directly off the main highway are Villa Altagracia, Bonao and La Vega. If you want to travel a bit further off the main highway, the towns that jalencastro mentioned, plus Jarabacoa are also options.
In most towns/cities in the country, other than SD, nightlife is non-existent from Monday through Wednesday. The action picks up a bit on Thursdays, but doesn't go into full swing until Friday. Of the places mentioned, Bonao, San Francisco de Macoris and La Vega will offer the most variety.
On most days, you will find the largest selection of women in La Vega, if you know where to look.
