As a solo paddler who uses a tandem rental as his "solo", the comments about weight distribution are dead spot on.
Weight distribution is important even in a tandem, but it's critical in a solo.
Paddling "backward" in the tandem, I have both packs, gear and food as far forward as possible. I start with the heavy food pack nearest bow, and swap out as it gets lighter later in the trip.
You want bow heavy into the wind, stern heavy with a trailing breeze.
I've found that I can slide packs to achieve that, but in narrower true solo, that might not be possible.
I think sometimes it's difficult to judge if your set -up properly especially if your in calm water sans wind. As the wind picks-up, you find yourself working way harder than you want and in some cases at risk for a dunking.
Since there's always a little water in the canoe ( at least when I paddle), I use that as sort of a " leveling bubble". I thought about gluing a small level bubble onto seat frame when I buy my own canoe.
That way I can see at a glance whether I'm set up right for the conditions without any guess work.
IF your thinking of trying the double paddle, you do need a longer paddle. I use a 9' paddle, any shorter your banging the thwarts and exaggerating your entry stroke.
I'm sure that once you get the load distribution worked out, ANY canoe will perform to its design limits. Working that out before you hit big water/wind is a good idea especially when your traveling solo