We actually stayed in Port Clinton and traveled over for the day a couple of years a go. We had our three yr old with us, so we didnt plan on hitting up the nightlife, although it was kind of fun to get there in the morning and see some of the hungover folks that missed their ferry the night before LOL. From what I have heard it is a blast to enjoy the night with everyone else on the island also wanting to have a good time and enjoy themselves.
We took millers ferry over, much cheaper than the jet express, and it was also nice to enjoy the 20 minute ride over (however their return service stops at 7pm if I remember correctly, but no need for that if you stay on Put in Bay). I would suggest renting a golf cart for your group, its just so much more fun to put around in on the island and see everything and enjoy the breeze without being squeezed in a hot vehicle. Last time we went they had carts that fit like 8 people at a time.
Heinemans Winery and Crystal cave was fun, you get a brief history of the islands wine making and the catawba grapes used in making wine. Also, the crystal cave is one of the largest known geodes on the planet (found by accident when digging), you get to stand inside of it and take pictures, with your purchase to both you also get drink tickets to sample wine.
The Worlds longest bar is located on the main street in town next to shops and across from the peir, they seem to always have entertainment there.
Perrys Monument was also pretty cool, you get a brief history on the war of 1812 from the park ranger up the elevator and then get to see the views on top of all the nearby islands, including rattlesnake island, which is listed as the most exclusively wealthy island in the world, according to the discovery channel. If I remember correctly, it is the 2nd or 3rd largest federal monument in the U.S.