I have been in the lower Niagara River a couple of times. Once with my dad in his 18foot Bayliner and once with mine. The trip with my dad was shortly after the guy fishing got sucked down under and drowned. My dads boat and especially mine, had no problems. As long as you keep your speed up and go directly through the swirl, it isn’t going to suck you under. I definitely could feel the swirl as I passed through it. But it couldn’t pull down a 5000lb boat. A little fishing boat drifting in the current, more than likely.
The two US launches on the River, one is in Lewiston and the other at Fort Niagara. If the water level is up launching won’t be difficult. But the day I launched mine at fort Niagara, it was low and I had to push the boat off the trailer beyond the ramp. I never went back. Lewiston would be a very tight fit. I’m not certain I can do a 180 degree turn. If I had my 1996 Bronco, I’d have a better shot at it. But the F150 is longer and makes it difficult in tight spots.
There is a great launch at Port Dalhousie in Canada. I would use this if I ever wanted to cross Lake Ontario to Toronto. It clears me of having to report to Customs upon my arrival cuz I already trailered over the border at Lewiston. Plus it puts me west of the shipping lanes for the Welland Canal. No monster wakes off the lakers. Good overnight parking.
Most of my overnight parking difficulties has mostly to do with the Erie Canal. If it absolutely necessitates, I can launch in Downtown Buffalo and cruise all the way from there. But then adding roughly 2.5 hours just to get to the locks.