From my hasty research, it seems that Kennabas and Canyon are the trickiest to land from the upriver side or pushing off to head back upriver due to strong currents, even at the portages. I don't think I'll get the chance to do any of this this year but hopefully next summer.

I know a member on this site who went through there the Spring that I was up there with his brother and their sons. On the way out, they detoured via Wawiag to avoid the dangerous currents and water levels at these falls.