We stayed at BCV during our last trip and spent probably a portion of every day on the Boardwalk. We arrived before our rooms were ready, so we walked over and had lunch and then just walked around for a little bit. One of our favorite restaurants ever is the Flying Fish, so hubbie and I went there one evening for dinner. Most of the other nights, the whole family, including my mom and four kids would walk over and enjoy the nighttime activities. The kids loved playing the arcade type games and winning tons of stuffed animals. They loved getting their faces painted. My six year old even talked hubbie into walking her over one night to get hers done again and that gave them some special one on one time.
We rented the surrey bikes several years ago, and hubbie won't do it again, as he was left at the end of the ride pedalling alone, lol.
We haven't done any of the adult entertainment because of the kids, but we do enjoy going and getting ice cream and seeing all of the live performers. We also enjoy watching the fireworks from the bridge.
If I weren't staying at a Boardwalk hotel, I would give it a couple of hours. But since you are staying at YC, I'll bet you find yourself over there more times than you planned. It is also nice just taking a walk around the lagoon, or the ferry from one resort to another.
Have fun