I visited Shennongjia on a Monday in June. I took a train from Wudangshan in the afternoon to Xingshan. It takes about 2.5 hours and involves a change in Xiangyangdong.
From Xingshan, I took a bus to Muyu from the bus station which is about 5 minutes walk from the train station to the right. The bus took less than 1.5 hours. It is a beautiful ride with pretty views towards the right side for most of the trip.
I did not have much information on Shennongjia before my visit, just that there are several scenic areas and that there should be busses. The guesthouse where I was staying did not have any specific information on buses either. The town street was under reconstruction in typical Chinese style, all the streets were being renovated in one go. Probably incredibly efficient but it was rather unpleasant to move around. The tourist transfer center was closed too, probably due to the road works.
So, not much wiser except knowing that I wanted to give priority to the Shennongding Scenic Area, I ventured out around 7 am next morning and randomly hailed a passing minibus. I was lucky as it took me and it went along the entrance to Shennongding scenic area for RMB 10. I paid my entrance fee (RMB 130) and bus ticket (RMB 60) without knowing what would happen next and waited in an empty bus, soon to be joined by a full tour group. The group was nice and I actually enjoyed their company. We made a tour of the scenic area of a little bit under 4 hours with 4 stops. The stops were quite short and it became quite busy towards the end. The busses stop at the same viewpoints and at the last two stops there were platforms with photographers who had speakers to lure, or intimidate, potential clients. I could also see that there are actually several circular cemented paths that did not seem busy, so this could be interesting when exploring on your own. You can enter the park by car and there were quite a few cars on this foggy Monday morning. I imagine the road can be jammed during the weekends. The views are beautiful, though it was cloudy and it rained when we started out. The fog adds to the beauty though. The road runs up to a height of around 2600 meters so it was pleasantly cool.
Our first stop was at the end, as I started to wonder if we would stop at all, at the rock formations. It then was followed by a stop at the military outpost, which should have a spectacular view but the distant view was hidden by clouds. Next was the view on the stone forest, of which we saw only a bit through the fog. Though it reminded me of the stone forest at Huangshan. The final stop was at the Golden Monkey Creek where we walked down a path along the stream but no golden monkeys there, just people.
On the way back I did not feel like taking a taxi so I waited a few minutes until a driver of an empty bus signalled that he can take me down and he dropped me off at the Xiangxiyuan scenic area. It is right next to Muyu town and this is not part of the core zone. It is a nice path along a stream with waterfalls which ends in a letdown, a new water station with plastic pipes in the water. They were still working there.
Next morning I took the bus back to Xingshan where I took a direct train to Chongqing, a 2.5 hour trip. I was glad to be able to visit this way but by renting a car or taxi for a few days one can probably appreciate the place in much more depth.