You can enjoy SWF without going to DC. There is plenty to do.
You'll be able to pet dolphins in the Key West area if you hang out and buy some fish food.
There's 2 thrill rides, plus all the shows. It usually takes about a day and a half to see everything.
DC is a special experience. For that, you need to schedule a complete day, and then it's good to have a few days after that, because your DC pass gets you 7 days at SWF and BGT.