@calypso726 did a great job pulling up comprables for flights. I'll say that I've found UA overall the easiest to use, points wise, especially since URs transfer to United Mileage Plus easily. I made up dates for a May trip (when there are usually the MTY-military discounts) and you could fly non saver (since it's only 2 months out) RT for 2 economy for about 130 UA miles OR RT mixed (economy to ORD, ORD to YVR) for 200 UA miles.
AA miles redemption tickets, especially if you're looking for more than one ticket, can be much harder to find, especially from a small market. However, I'm sure you've seen references to the grAAvy train and so it is fairly easy to rack up some AA miles there. The danger is always having a lot of miles you can't use.
Much as I love Delta, they surely do want a lot of skymiles (normally) for a flight so that might be the last ditch currency. I just priced the same flight dates in May (*granted all the less expensive awards are long gone) and for 2 people RT it would be 181, 000 Skymiles for economy comfort, 170-ish for economy.
Personally, I'd keep hoarding URs and consider ditching your family and get an MTY for a May Alaska cruise (usually the first cruise of the season will have the MTY and it's a great deal). Joking, sort of on the ditching family. But...I would keep an eye on the MTY rates for
DCL, there are usually several at any one time but especially right before summer. DH and I have no shame using them

. If my DD weren't graduating in May, I'd be booking the transatlantic one in a heartbeat!