Tolls are pretty hard to avoid in the NE. I'd suggest getting an EZ-Pass account and tag which means you just drive through the booth and the RFID transponder just dings you for the toll, with an auto refill of the account via linked credit card. Yes, the GW Bridge is expensive to cross, and traffic on the Cross Bronx (I-95) up through Westchester and onto the Connecticut Turnpike is just brutal for about 20 hours a day.
A much better way is up the Garden State Parkway in NJ to the NYS Thruway (I-87/287), over what was the Tappan Zee Bridge (now named after Mario Cuomo) to I-684 to I-84 East through Hartford and onto Massachusetts. If any of the route is going to coincide with rush hours (6:30-9:30am and 3:30-7:30pm), I will even take a bigger detour and do the Thurway the other direction north almost to Albany and pick up the Mass Pike extension (I-90). 60 miles further and most of the time a shorter trip timewise due to no traffic. Really nice scenery just about all that ride too.
Big warning: The only "parkway" you can tow a trailer on anywhere in the northeast geography is the Garden State Parkway in NJ. Huge no-no with big tickets and fines on any in NY, as well as the Palisades Parkway in NJ. Also, low clearance bridges.
On edit: I posted before reading to the end of the thread; still, cannot stress the importance of staying off the NYS parkways and the Palisades.