One idea is the OneWorld award, using AA miles your trip could be done for 130k miles/person in business. Doesn't help with using up the BA miles, so perhaps your plan is actually better in that respect.

I'm not too knowledgeable on this, just researching myself, but I know the Oneworld awards allow free date changes based on availability, perhaps an advantage? Good info at http://www.flyertalk.com/forum/ameri...er-awards.html if you're interested.

I'm looking at a similar trip, may consider your idea for using up BA miles.