Well let me add my $.02.  
Tracking
I think your sawyer is a little longer making it track straighter. But I do not understand why it should take more correction in the prism than the sawyer. On second thought If the sawyer is wider do you tip it  toward the side you paddle on? Some boats turn a little when tipped.
Wind
Every solo except my robroy (almost a kayak) has been sensitive to where the weight is in wind.  Before I had a sliding seat I kept a pack in front of the canoe that I could move with the paddle.  Head into the wind and push it forward.  Get a tail wind and hook the pack with the paddle and pull it all the way back between my feet.
Seat position
With a slider seat I get to try a lot of positions.  It may not be the fastest position but on calm water I like the way the canoe handles with the stern a little heavy.  
Tripping solo boat size
The robroy is a little small and sometimes a hassle to get every thing in and out of. I am some times cramped with a pack between my legs.
The magic is probably a little to big.  It would be easier on the portages and probably faster on the water if there was not so much of it.  NO I will not sell either one.