Your concerns and thoughts are right on the money. I used to run the 6665 hesston. Fine head for its day. Then went to the Macdon 932 auger head. Vast improvement. Still, a lot of shatter damage in the fescue and ryegrass. This damage is not all the fault of the auger, it is largely the reel size and design as well.
Now running 2 Macdon 972 drapers. The larger reels turn slower and the drapers are very passive at transporting the grass to the opening.
It's highly unlikely that I will ever go back to any type of auger header. However, one thing you will need to do before season, is remove a draper canvas a time or two so you know exactly what it takes to replace one and keep an extra canvas on hand.