Takeda Castle Ruins in December

Hi,
Will be in Kyoto this mid-December. Thinking of visiting the Takeda Castle ruins. However from the japan guide information, the Tenku bus operates from March through November only. With the bus not operating in December, it means it will be a strenuous ascent that takes about 40 minutes and can be slippery after rain. The best time to view the floating castle is in October and November
So i am just wondering is it worth my effort to visit in December (opens from 10am to 2pm) ? Would i be able to view the floating castle ?

Unkai, a sea of clouds, could be seen in the early morning from late September to early April. The possibility is once in three or four days. The best is around one hour after sunrise, say, 7 AM. The Unkai will disappear in about an hour. No chance when you come there as late as 10 AM. The thickest unkai could come out from late November to early December. Snows from late December to late February, which make the site dangerous.
http://www.shirofan.com/shiro/kinki/takeda/unkai.html
http://guide.travel.co.jp/article/3051/

One of the best places to see the floating castle is Ritsuunkyo, not at Takeda Castle itself. There are three observation decks at Ritsuunkyo. The first observation deck is regarded as the best.
http://www.shirofan.com/shiro/kinki/takeda/ritsuunkyo.html

So, Mid-December is rather ideal. But you need to stay in Takeda or nearby. The first train from Kyoto could reach there by no earlier than 10 AM. Kinosaki Onsen and Himeji could be marginally OK. The first train arrives at Takeda at 6:54 AM and 7:18 AM, respectively. Then, take a taxi to Ritsuunkyo. After the unkai, you could visit Takeda Castle by Tenku Bus or on foot. Two other trails to the castle are not that steep. Many people sleep in the car in a parking lot until the dawn. That is thought to be the best practice to see Unkai.
http://www.city.asago.hyogo.jp/takeda/0000003453.html
http://www.city.asago.hyogo.jp/takeda/cmsfiles/contents/0000005/5204/a...
https://world.jorudan.co.jp/mln/en/?p=0&xpd=1&from=kinosaki+onsen&to=T...
https://world.jorudan.co.jp/mln/en/?p=0&from=Himeji&to=Takeda%28Hyogo%...

6:54 AM is to be 7:15 AM.

Hi Luisjp,
Thanks. That's really good detail information provided. Appreciate it!!