I would avoid going to Cedar Point over the weekends if possible. You should check into staying onsite for the convenience of walking to the park, they have a couple resorts and new cabins. A nice plan is to stay at least 2 nights....enter the park on arrival day with a discounted after 5pm ticket, then the whole next day at the park, then a final day relaxing at their waterpark (Soak City) and beach. Check CP's website or Facebook for package deals with tickets/resort.
The animal safari is a fun unique experience, just be cautious that the animals come right up to your car. They will stick their head right in the window and get slobber everywhere. There have also been reports of them damaging cars with their antlers etc.
Another idea is to check out the Islands around Lake Erie. There are boats and ferries leaving from a dock near Cedar Point. Check out Put In Bay and Kelley's Island. If you are bringing kids you might want to avoid them during the evening due to the party atmosphere....but it's a fun place to take your family during the day. Check out Goodtime Cruises out of Sandusky Ohio for daytime island hopping cruises.
I would also look at Kalahari Resort in Sandusky. It's a huge indoor/outdoor waterpark. They also have an animal park, rock climbing wall, zip line, arcade, pottery place...etc.
What airport are you coming into? Niagara Falls is pretty far from CP. Around 5 hours I think.
Have fun!
