Yampa and even Green down to Split Mountain (my opinion for what it is worth) should be do able for reasonably loaded canoes at the current levels of the Yampa.
Split Mountain tho is gonna depend on how much water the Green has coming down.
Lowest I have done Yampa is around 3,000 cfs maybe a bit less and tandem canoes should have handled that pretty well. Even if you did fill up the canoe with water, reasonably competent boaters could recover after a swim and a bit of help. The Green on that trip bumped up the flow to around 5,000 cfs more or less. I remember Split Mountain rapids having some pretty big whoop de do wave trains at that level. Not a problem in any raft, ducky or kayak but (again my opinion ) in a loaded tandem canoe some long swims would be in order just from wave swamping over and into the tandem canoes.
You might consider a couple gear boat rafts for the heavy gear and lightly load the canoes with mostly personal gear dry bags that would easily float. My take on lining canoes in Split Mt is gonna be pretty sketchy if even possible on some drops. Split Mt is pretty big and wide normally but again I have not seen it lower than 5,000 cfs or so.
In any event, doing that float in a canoe would be a hoot if weather was nice and warm.