We too stayed at Branches
http://www.branchesofniagara.com/ in early October last fall. Stayed 4 nights. It's a very nice campground and an easy commute to Niagara. Parking spaces are fairly big so you aren't camped right next to people on each side. We didn't have a Toad so we rented a Cruze from Enterprize for about $35/day. They picked us up and dropped us off at Branches on each end of our rental. Routine thing for Enterprise.
You will definitely want to see the falls from both the US and Canadian sides. Each offers a completely different view and you will appreciate visiting the Canadian side of Niagara.
Take part of a day and go see Old Fort Niagara
https://www.oldfortniagara.org/ for a cool step back in time. On your way back, cross over and spend the afternoon at Niagara on the Lake. A quaint little shopping village with nice bistros, good dining and even nicer shopping. No need to spend money just walk the sidewalks and watch everyone else spend theirs. There are several wineries in the area with $5 wine tasting.
Parking down town (State Park Area) Niagara on the US side was no problem. Plenty of parking spaces all day every day when we were there. Obviously we had a small car so it seemed pretty simple but we saw plenty of full sized rigs in the area too. As others have posted Seneca Casino is only 3 blocks from the falls so there is good parking there too.
Don't be afraid of crossing over into Canada. Customs took less than 5 minutes each time and we went 4 or 5 times at least.