What you want is very easy to achieve for very few miles (less than 200k/person for sure). Actually, it should only cost you 135k.

The one thing you'd need is a few more AMEX MR points (which you can transfer to AC's Aeroplan program). The beauty of Aeroplan is that they allow you to make TWO stopovers IN ADDITION to your destination.

So, if those are really the only stops you want to be making, you can book that through AC, no problem. Routing would be tricky, but many many people have made "mini rtw" trips on AC miles thanks to the two-stopover-rule.

Think it's a bit too much of a hassle? Check out that link in my signature

But seriously - there's no need for you to spend 2 or 3 HUNDRED thousand miles on this itinerary!