On my tripping boats I have them in the bow, butterfly coiled held on the deck with bungie, they are one and a half length of the canoe roughly.... At the stern if traveling in places where there is chances of a swim I put a small throw bag under bungie, in moving water if you end up in the drink 60 feet of rope gives you a good chance to reach shore before that boat stat tugging at you!!
I don't use the painters for other things than painters, If I need winning or tracking , I use proper lining ropes mounted on a bridle with the line centred on the bottom of the hull.
As for around camp for tarps etc, I use dedicated ropes that have prusiks permanently attached to it, make tarp set up a breeze!!