Everything that Craig said, and then some, although when I was at Peggy's Cove 27 years ago it was early morning and we nearly had the place to ourselves. Guess things have changed over time
We've taken a motorhome to the coast 3 times now and every trip has been fantastic. There's just sooooo many beautiful places to see you'll never even come close in one trip but you'll have a fantastic time seeing whatever you can.
On one trip we took the St. Lawrence River route and crossed down into New Brunswick and then did PEI and on 2 other trips we took the ferry across Lake Champlaine (sp) then went thru Vermont, New Hampshire and up into Nova Scotia from there.
Whatever route you take you'll have one of your best vacations ever and meet some of the nicest folks you'll ever come across.