Be sure to get the hotel to arrange a transfer, it's cheaper than getting a taxi from the airport and ensures they'll take the highway direct (approx 1.2 hours) and includes the road toll charges.
I only had 1.5 days here by the time we flew in and out early the last day, but would have liked at least 3 - 7 days so you can do activities also enjoy relaxing at the hotel in the pool.
Hotel has free bikes, so definitely ride into the town it's really lovely even in the heat and the roads are pretty flat so you're not having to ride back uphill.
Light show was amazing - take your rain jacket/umbrella in case it rains as you'll get soaked if it rains, as it's an outdoor theatre.
Bamboo raft ride, the mountains/hills are amazing but once you've seen some you don't need a two hour ride (which is on a plastic raft not bamboo by the way), I think 1 hour would be fine. And give you more time to do another activity.
Get a massage! You only need to give the, 1/2 heads up for it and well worth the money.
We stayed two nights and enjoyed our time greatly. The room is quite pleasant, and staff very friendly and helpful, and the food served in the roof top restaurant was excellent whether it was Chinese or Western dishes. You can't beat eating a delicious meal while viewing a grand range of karsts marching off into the distance.
We rented bikes from the hotel and got some help from the staff in planning our day trip. Those memories made during our stay in Yangshuo will last a life time.
"Great hotel outside of town in renovated farmhouse"
I stayed here for 3 nights and really loved being here. The room was renovated, it was part of an old farmhouse. It was done very well with big rooms, cool bathroom set up and fixtures. Staff were exceedingly helpful and pleasant. I even ran into one of the staff in town and she helped me make some additional connections that were very helpful and it was her time off. Itwas really nice to be out of the busy town in a peaceful setting. I spent a lot of time on the roof drinking cool drinks, Writing emails, and meeting others they also arranged two days of bicycling for me which I really enjoyed. This was a great place to stay!