I have Bowfished for lots of years out of a canoe. I have no problem standing up and shooting fiish. No out riggers on my 17 ft aluminum canoe. I have shot several of the Illinois Bowfisher's tournaments including this years Carlyle Classic beating out several of the 3 man teams. You can get into a lot of shallow water where the big boats can't get to. Mine will go in about 3 inches of water.
Don't plan on winning to many number tournaments in a canoe but you do have a chance to win in a big 10 or 20.