+1 for Princess Louisa. Big long public dock for easy tie up. Provincial Park has half a dozen lovely shaded sites with tables, firepits, water and outhouses. Virtually everyone stays on their fancy cruising boats and we've never seen anyone else camping there in our half dozen trips. Zero camp fees too! Takes roughly two hours from nearest gas dock at Egmont.
Malibu Rapids are comparatively mild. Cruising boats need to be cautious in the swirly water as it's narrow and you can't see the entire length of the rapids. But faster planing boats can transit safely at all but the strongest tides.
If it was road accessible, Princess Louisa would be one of the most visited and photographed places in Canada. Stunning scenery and so tranquil, like a cathedral in there. Worth going in wet weather because there are something like 70 waterfalls running.