East Providence is a fair-sized city, and just like any city it has its "nice" and "less nice" sections. It's almost entirely blue-collar to middle-class and the predominant populations are Italian and Portuguese. Crime rates are relatively low. "Locals" would know of good stores and restaurants and such, but nothing exists that makes East Providence a destination.
The East Side of Providence is a different story. It hosts Brown University and part of Johnson & Wales College. Thayer Street is "where it's at," with lots of shops and restaurants and coffee places and so on. The neighborhood's residential blocks have everything from large brick apartment buildings to Victorian mansions. Around Benefit St and Blackstone Blvd are the swankiest areas of Rhode Island's capital city. Sometimes the accumulation of litter along Thayer and Waterman Streets can be annoying, but by and large the East Side is well-kept. Providence as a whole is in the midst of a revival, from its nicely renovated train station and bus hub (Kennedy Plaza) to the thriving and gentrifying Federal Hill neighborhood. But particularly on the South Side it still has a ways to go.
I thought I'd offer "sketches" of both East Providence and Providence's East Side in case you said one and meant the other. Either place should work out fine for your visit.