IMHO I'd recommend you keep saving up for at least business. We save for F mini-RTW's and while we are saving and have to pay ourselves, we take the shortest direct route possible since we are in Y. For example earlier this year we flew YYC-YVR-HKG-BKK on our own dime in Y. In a couple of months we'll be on YYC-SFO-FRA-BKK which is a lot longer but in the lap of luxury.

Also the AC legs and LHR destination will mean your "free" reward trip will cost you hundreds of $! Avoid AC and LHR if you can. There's (free) ways to find alternative routes other than the Aeroplan website (ANA tool, award nexus). Aeroplan loves people to take the awards flights that make them even more money and their search results reflect this.