I agree that a 12v 55 would likely make you happy. A bump to a 24v would be better, but you have to weigh in the costs associated–additional battery ($ and weight), additional bank for an onboard charger, etc. I had a 12v 55 on a similarly sized Sylvan, and it worked well for me.
This is good advice, and is the main reason why I only went with a 12v 55lb Terrova a few years ago for my boat. I liked that 12v is more simple wiring and charging, less weight and storage, and cheaper. My boat’s specs are 848lbs, plus a 60hp outboard and all of the other stuff, so a little heavier than your boat by a couple hundred lbs. I primarily bass fish and on smaller lakes so I very rarely have the speed above 5 (1mph). I think my top end speed is around 2.4mph on calm water.
I would say that the 12v 55lb Terrova on my boat has been more than suitable 90% of the time. The 10% is when I have trolled crankbaits with just the Terrova and it’s tough to get the desired speed if there is much wind, and if I’m working into a stiff wind. Frankly, if the wind is too much for the trolling motor, it’s unpleasant in general.
And I completely agree that the Terrova is much better than the Powerdrive.