We've done both trips mentioned above. We live in the Yukon, so have ridden the highway numerous times. The road from Watson Lake to Meziadin, Steward-Cassiar highway, is a nice trip, but can be slippery/muddy at times as it's not all chipseal. I would suggest doing it during the drier months around June/July, then back down the Alaska Highway to Calgary if you ride up and back. Take the Inside Passage if going by ferry either Northbound or Southbound, and choose between Stewart Cassiar hwy, or Alaska highway on the other leg of the trip. Stewart-Cassiar is pretty scenic, but then too is the Alaska Highway.
E-mail me when you decide to go through the Yukon. We live on the border of the Kluane National Park & Reserve in Haines Junction,Southwest Yukon. It is . one of the most scenic spots in the Yukon. Another great ride is the Haines Highway, connecting Haines Junction to Haines Alaska. The road goes through Yukon, British Columbia and Alaska within about a 3-4 hour liesurely ride, excellent scenery, mountains, glaciers, Bald Eagles, moose, grizzley bears, lakes, mountains, Alpine Sub-Arctic to boreal forests. Big recommendation to take a day out of your busy schedule. If you overnight in Haines Junction and leave about 6AM, you can go to Haines and back by early evening. The best time to travel is early morning, 5-8AM for Grizzley Bears and evening for moose & bears about 5-9PM for wildlife sitings. Excellent photographic opportunities.