I-95 North to South

I might suggest that you pick-up I-90WB in the Boston area, to I-84WB into NYS. From here, you could either head south on I-87 to I-287 as you mentioned, or head a bit further west and either turn south through the Delaware Water Gap (beautiful National Park) or further west to p/u I-81SB. From this area, you can pick multiple routes that will take you south of the DC area, without the NYC, NJ, Baltimore, and DC traffic nightmares.... I-78 to Harrisburg, then south on Route 15 (a 4-lane divided highway for the most part, are routes south that we've used multiple times! I like that one for the OTHER reason that it takes me past the Cabela's, in central PA. No better place to stop for a drivers break!