Don't think I've mentioned it yet, but here are the excursions we have planned:
Portland, ME — no tour booked (we'll probably go ashore, find something to eat, maybe ride the narrow-gauge railroad. Maybe not, we'll see.)
Bar Harbor, ME — 4-hour Private Guided Tour: Acadia National Park & More (small group tour, Viator)
Saint John, NB — Saint John Highlights (small-group, I arranged this directly)
[Bonus: Glass blowing demonstration]Halifax, NS — South Shore & Peggy's Cove (small-group, arranged directly)
[Bonus: Pewter making demonstration and building our own souvenir pewter item]Sydney, Cape Breton, NS — 6-hour Cabot Trail Tour (small group, I arranged)
Charlottetown, PEI — Private island tour (small group, arranged by someone else)
La Baie (Saguenay Fjord), QC — Back Country of the Fjord & National Park, (joining the large tour, purchased directly)
Québec City, QC — overnight, explore at our own pace (no tour booked)
I've learned over the years not to pack the days full, and that I prefer small-group tours. We've left some open time purposefully — I call it "serendipity time."