...as is Kayak.

If you restrict yourself to EWR departures only, you are probably limiting yourself to BA, Alitalia and Lufthansa unless you are happy with more than one connection. You might want to consider nearby airports as well for better deals.

You might also want to consider the connecting airport in Europe that you would have to use. You have ruled out FRA, LHR is unpopular but in theory(!) all the problems will be over when BA moves to T5 in March, CDG is also widely loathed (though I've never had a problem with it). Zurich and Vienna are nice airports to transit, and tend to have good connections to South East Europe.