The three concerns about going over the weight limit are tongue weight, braking and power. The weight distribution hitch will help with the tongue weight.
From some quick research I don't believe that trailer has electric brakes. Of course they can be added and of course you can add an electric brake controller. Combined they will cost you close to $1000.
As for power, the biggest issue is heat. Add coolant and transmission fluid gauges. An auxiliary transmission cooler is also a good idea.
You should not have problems with your east coast trip. Crossing the Rockies is another story.