Aeroplan is great as far as being able to get status easily, and its earn rates that haven't been degraded (i.e. still get 500 miles on the cheapest tickets for many carriers) but the redemption rates are rather poor, and some of the nifty features of other programs aren't there.

I'd hesitantly second the suggestion to look at bmi Diamond Club, though. I've been using it as a secondary program and my girlfriend's primary, and it's been great so far. Only a few downsides to it, but there's a lot of benefits in the near future.

On the plus side to DC:
- Miles + Cash. Can't say enough about Miles + Cash!
- Decent earn rates on flights, but great earn rates on things that aren't flights. Hertz rentals (when they post) start at 1700 miles/rental.
- There's been a new survey every few months for 2500 miles, which is how I've been able to build up close to 20k miles without ever crediting a flight to BD.
- Membership year based on when YOU cross the line, so if you join in December, your first month's travel isn't lost when the year rolls over. This may help you with the Christmas flights.
- Soft landings if you don't make the status cutoff for the next year.
- One-way awards are not only bookable, they're encouraged.

On the minus side:
- There's not a lot of benefits if you're based in NA. Most of the easy ones that you get with Blue+ (fly 3k in a year) are only on BD metal, and all the benefits you'd likely be able to make use of if you did hit *G (and at 2 flights a year to the EU you may be able to) require connecting in ORD at best.
- Uncertainty of the program. I'm just hoping it holds out long enough that I can use up these miles we're earning.
- I haven't done the math, but the earn rates seem to be lower than Aeroplan for the same flights. I do know that its far more profitable, as far as earning status goes, to credit the low-fare BD flights to Aeroplan.

Now, if you think you can swing 35k miles a year, then Aeroplan is a decent enough program, not to mention the fares US-YYZ-Europe are often a lot better than the fares YYZ-Europe, and YYZ is a fine for transiting these days. Plus domestic lounge access in the US, unlike (afaik) most US-based carriers.

But other people may have more opinions.