Visit Japan advice on Itinerary

I am planning a trip to Japan in October and planning to visit Osaka, Kyoto and Tokyo.

From Osaka, i wil travel to Tokyo, visiting the Fuji Five area first.

I checked the timetable and decide to head to Tokyo Shinjuku first to place my luggage in the coin locker before taking train to Fuji Yoshida (Oshio Hakkai) and then a night stay at Kawaguchiko

Train from Osaka to Tokyo Shinjuku (overnight luggage deposit at coin locker)
- JR train to Oshino Hakkai and then Kawaguchi for overnight stay

Next day: Explore Lake Kawaguchi + Lake Sai , Tenjosan Park (purchasing retro bus pass)
- Bus to Shinjuku Tokyo (dinner at Shinjuku) and collect luggage for hotel check-in.


I know i can take train to Gotemba and then bus to Oshino and Kawaguchi. I calculated the time and decide to head to tokyo first to lessen my luggage load since the time duration is not big between the 2 routes.

Any comment? Is my plan workable?

Thanks

Train from Osaka to Tokyo Shinjuku (overnight luggage deposit at coin locker)
- JR train to Oshino Hakkai and then Kawaguchi for overnight stay

There is no JR train to Oshino Hakkai! JR trains only go as far as Otsuki. From there you would have to take a non-JR train to Kawaguchiko and then a bus to Oshino. Alternatively, you could take a direct non-JR bus from Shinjuku to Oshino Hakkai (advance reservation recommended on busy days).

However, you can save several hours by not making the detour via Tokyo and get off the shinkansen at Mishima Station, instead. As for the luggage, you could use a delivery service to send it from Osaka to your next hotel in Tokyo:
http://www.japan-guide.com/e/e2278.html

"There is no JR train to Oshino Hakkai! JR trains only go as far as Otsuki. From there you would have to take a non-JR train to Kawaguchiko and then a bus to Oshino. "

I read that to access Oshino Hakkai, i need to take a train to Fuji Yoshida and then a bus ride to Oshino Hakkai....

Or is it easier with a bus ride from Kawaguchi?

I think the easiest is the direct bus from Shinjuku. Otherwise, I believe that you can catch the bus to Oshino at Fujiyoshida Station or Kawaguchiko Station.