My wife, cousin and combined 4 kids spent 5 weeks on the road in Canada and Alaska last summer. Left Portland without a single reservation. 14 days later they were in Anchorage. I told them they could have made it in 7 days and their reply was they had fun and enjoyed themselves.
I can't comment on caravans and their particular benefits but I wouldn't be intimidated by the Alcan - it isn't the 60's when my Grandparents first went up it. It is comparable to any good 2 lane state highway in the Lower 48 and better in most areas. If 2 Moms and 4 young kids can make the trip in our Ford F-350 and Bigfoot camper I suppose anyone can.
