Is there some reason you have to get on the 495 loop? The reason I ask is that Wilkes-Barre seems like it's far enough from DC that you could take a route that goes straighter into DC.
495 always seems to suck, and I've never understood why. Even when I lived in DC for 4 years I tried my best to avoid it, even on weekends, and I knew ALL the traffic patterns then.
If you are going during a non-rush hour time, 395 isn't all that bad, and avoids 495 because it turns into 95 once it crosses the 495 loop south of DC. Unfortunately, 395 doesn't completely traverse DC. But you can get to it pretty easily from the Baltimore-Washington Expressway (295), or Highway 1.
If you are hitting DC anytime close to a rush hour, though, 495 isn't really any worse than any other road in the DC area. Non-interstate roads in Northern VA tend to be light-filled, congested and confusing, at least during rush hours. During non rush hours, those lights will slow you down versus just staying on an interstate road.
Sorry, but DC just hasn't figured out a decent traffic setup. And it's hard to completely bypass DC on an interstate unless you stay on I-81 from Pa. then take 64 east from Staunton to Richmond, but this is an extreme variance from 95 just to avoid some traffic.
DC is a bottleneck in the worst way.