The Fort will spoil you on other campgrounds, that's for sure. I hope you love it as much as the rest of us do.
I would suggest scrolling through this site and reading up on people's trip reports. You will learn a lot that way about how people spend their time at the Fort, and some things will sound really interesting to you. We like to plan our trips by spending more time at the campground than at the parks. Lots of people do the opposite, spending most time at the theme parks and just a day or so at the Fort. To me, the Fort is pretty much a destination in itself. Bike riding (bring the bikes if possible!), fishing, canoeing (they rent canoes), walking, riding the boats and monorails to check out the other resorts. Most of that stuff is free! Cooking at the site, but dining out is fun too. The campfire/sing a long and movie is held every night and that is a blast. You can watch the Magic Kingdom fireworks and the Electric Water Pageant every night from the beach. The pool has been upgraded now with slide and splash zone. There really is a ton to do before you even step foot in a park. But, of course the Magic Kingdom is a boat ride away!
If your budget allows an expensive dinner show, by all means book tickets for the Hoop Dee Doo, and do it as soon as the reservations open up. For an April trip, it will probably be any day now as they are going back to 180 day reservations tomorrow. It's not a cheap night (probably around $300 for your family!), but is so AWESOME! We've done it twice and my girls think it's the best. So do I!
Well, others will be chiming in with their ideas for you. Have a great time!