I would classify the neighboring town of Wappinger as being very similar to the Town of Poughkeepsie, almost to the point where they're indistinguishable. Wappinger doesn't have the population of the Town (about 27-28k if memory serves) but in terms of development, they're very alike.
The Town (not village) of Fishkill north of I-84 also reminds me of Poughkeepsie, though that's at about 22k people. Hyde Park's population is close to that of Fishkill's, but there are some really wide-open spaces there up near Staatsburg and going north towards Rhinebeck, so it doesn't remind me much of the Town of Poughkeepsie much.
You won't find anything with the population of the Town of Poughkeepsie though, as it's the most populous municipality in the county -- even more people than the City of Poughkeepsie -- but if I had to compare it to any other town nearby, it'd be Wappinger.
