So long as no-one is in mortal danger I would consider any location as a possible venue for a humanist ceremony.
I know one couple who married on top of a cliff and abseiled their way down to their reception on the beach. I married a couple at sunset around a desert oasis. A decommissioned church set in the rolling hills of the Cotswolds is another favourite. In canoes in the bay of a Cornish village isn’t too crazy an idea if it’s relevant to you and makes you happy. When it comes to your wedding day, you should have the opportunity to have it reflect you the best way that it can. You share the dream, I’ll help make it happen.