Of course you know the safety stuff, which cannot be overly emphasized.
One item we ALWAYS use is our water proof gear bags and all our stuff gets attatched to the stick thingies that cross the canoe between the seats.
As to your casting concerns and distance......balderdash. We had a "distance guru" in the club at one time. After his expounding to us the "need" for greater distance and the method of attainment (practice) and "what would we do if we could not reach the fish?", he merely shook his head and wandered off when we told him "Hell, if we can't reach the fish, we'll just move the danged boat!"
Amazing, but it still works.
.....lee s.