I'm almost exclusively a river/creek guy. I fish ponds occasionally and lakes very rarely. I've been to EF before, but never fished it. Your best bets for saugeye will be any of the Ohio River tributaries or spillways below any lake that has them. If you're willing to drive, Indian, Buckeye, and Alum lakes are some of the best in the state. All are around the Columbus area.
As for flatheads, I don't eat any fish for the most part so can't comment on that. Please consider releasing any under 24 inches though because our local waters are getting gutted by paylake people. It's becoming increasingly harder to catch one over even 30 inches. I typically use artificial lures for them too, however, I will occasionally use live bluegill or chubs. The best luck for me has been to hook it through roof of the mouth and out the nostril. The hook is attached to a roughly 18 inch leader with a barrel swivel. On the other end I'll thread the line through a flat, slip sinker. Usually 3-6 ounces depending on current. Just toss this out in the current or eddy and wait.