Canoeing is as much about aesthetics as function, so we should enjoy doing things in them. Personally, since I'm now more than my nine pound birth weight, I don't enjoy paddling solo in the stern seat of a long canoe with the bow sticking up in the air. Paddling solo in the bow seat, facing forward with the stern sticking up in the air, is a lot more challenging.
Name them.
The biggest advantage is that you are seated close to the gunnels for more ergonomically comfortable paddling on both sides without moving.
Second biggest advantage is that there is less yaw, so less energy is spent on correction strokes or switching.
Third advantage is that it does the same thing as heeling a boat over, shortening boat length and getting you closer to the water. It is more affected by the wind but I find it easier to balance being in the middle (side to side) and having access with the paddle to both sides of the boat equally without moving or changing balance. I also find it more maneuverable than a heeled boat and it gets you closer to the water.
Another advantage I find which is related to yaw mentioned above is that it only takes a slight breeze on the off paddle side to keep you going straight without as much correction or switching. Also in a tail wind I sit even further back in the seat rasing the bow even more to catch more wind with the hull acting as a sail.
Another big advantage is how maneuverable the boat is with the bow out of the water, this may also help with royalex boats with blunt entries with skid plates on them.
It is not a position for beginners, I wouldn't recommend it to anyone who doesn't have a good brace.
I also wouldn't recommend heeling a boat over to a beginner.
It's also not in the stern every time I go out, I started paddling this year in early March but didn't use the stern seat until about two weeks ago when I felt that an emersion wouldn't kill me. If the wind is up I also don't use it. I may also move back and forth from the stern seat to the rear thwart during a paddle depending on the wind.
I recommend any skilled paddler give it a try in the right conditions to see what they are missing.