Guess this classification is applicable to everything? ... how about "two kinds of people", the kind that are alive and the kind that are dead?
It should be really good adventure, go for it. If I would have a chance, I wouldn't hesitate, we all live only once On practical side, 2 cameras with 2 zooms, probably 24-70 and 70-200, for full frame, no time to change lenses. Both cameras secured with belt or line, so they wouldn't fall out. VR may help with framing, fast shutter speed, start with 1/1000 and shorter. Have a fun. Share pictures with us later.
Yes, unless I chicken out when I get there; or Covid would deter me from getting there this year; but this would only delay it because I don't plan to cancel the trip.
I was living in Niagara Falls for two yeas, never tired to photograph it. Another advice, have polarizer filters for your lens, don't think it would be practical use them on helicopter ride, they cutting light and you will need high shutter speed, to minimize vibration. But for the land shots polarizer probably can help a bit to reduce softening effects of water spray.
I note that billionaire politician Olivier Dassault was killed yesterday in a helicopter crash in northwestern France, and he wasn't even trying to photograph.
You've already shot from small planes, but when I did this many years ago with film, I found 35 mm woefully inadequate. The amount of fine detail was just too much for it. I find a similar thing happens on some landscapes with my Z6. Take the Z7!