Oh I agree…
I think on the Supernova they are 200-250 over if you want a boat that still performs. I am assuming for a 1000lb they are probably 250 to 300 ambitious. so … 700lbs.
Comfortable kids
…squirm less, so good kid seating is probably worthwhile.
We won’t be camping IN the canoe. We will be camping UNDER the canoe, if you can even call sleeping in a truck camper “camping”. I suppose it’s possible that one day we might try something like that but it seems like we are getting softer and more spoiled as we age and not the other way around. 
or
I used a folding chair like this one when my kids where too young to paddle:
http://www.campmor.com/outdoor/gear/Product___41293
It is more comfortable than sitting on a pad, keeps the center of gravity low but keeps them up out of the bilge water.
The metal legs can leave some minor scratch marks on the hull bottom, so if you get one I would pad the legs where they contact the boat with duct tape.