That back current at Hidden Falls can be tricky. Even with guides it takes some skill to nail it when the current is really moving. I’ve helped others that struggle with it and gotten help a few times. Seems like most people that use that launch understand how tricky it can be. The sand/gravel on the north side of the launch is ok to park the boat. You have to be really careful in high water because there are some rocks there.
The launch at the state park is nice and protected. For Watergate I think you need to call ahead and get a code to use it on the weekends, especially early or late in the year.
Off topic…..There is a good group of people that live at Watergate year round….very helpful if you have troubles. Last year I took my lower unit out by the confluence right before dark on a Sunday. I was able to get to Watergate with the trolling motor hoping someone would be around because it was early March. Guy that lives there gave me a ride to Hidden Falls to get the trailer and then helped me load the boat up. I only had to give him a couple of Mich Golden Lights for the trouble.