Corrections.
When you get down here locals will appreciate local spellings and terminology.
Saint John, NB vs. St. John's, NL
Maritimes = the 3 provinces which joined Canada in the 1800s., namely New Brunswick, Nova Scotia, Prince Edward Island. & of course, the conference that started Confederation was in Charlottetown, PEI, hence the term, Cradle of Confederation.
Atlantic Canada = Joey Smallwood's term to add in the province of Newfoundland and Labrador, which joined Canada in 1949. Per your trip outline, you are just visiting The Maritimes. Your trip would need to be at least 2 weeks longer to include all 4 of Atlantic Canada's provinces.
Your trip is yours alone. It is what pleases you. This is beautiful part of the world. You're bound to miss parts you would enjoy. Be flexible. Think, we might want to change.
Enjoy
:B