The garden is gorgeous! There are workers fixing something and taking care of the plants pretty much all the time. The area is vast and full of nice green grass and flowers. You can spend here whole day and it won't be enough.
The best views in Thailand for sure. Rent a good motorbike, you don't really want to loose time on fixing it all the time. We made it in 5 days and wasn't long enough, people are nice even though they don't speak english they try to help. Rooms are fairly cheap, no need to prebook, just have a look beforehand where you'd like to go. Roads are fine, there are 7 elevens everywhere, mini gas stations too so no need to worry.
Pleasant hike although quite slippery so better leave your flip flops in the hotel. Water is refreshing and I liked how there are rocks steps underneath the waterfall that you can actually walk on.
This waterfall is massive and impressive! Definitely the best one in Thailand. The water runs down loudly and you can imagine how strong it is. Do not skip this one.