My wife and I enjoyed this park very much. There are a few mapped hikes you can follow, but you can also go scrambling.
We started on the summit trail. It took us about 30 mins or so to get to the top at a moderate pace. It can be challening if you push for time. The granite is not slippery at all.
Once we arrived at the top, we took a different, undefined route back. It was very fun. There are plenty of interesting sites to see.
The park was crowded. Get there early and bring your camera.