15-day Japan Itinerary

I have got 15 days to visit Japan, arrival Narita 2:40 PM of 26 Sept'14 and departure Narita 3:50 PM of 10 Sept '14. The part of the tour confirmed so far is 4 nights stay from 26 Sept in Tokyo.
From 30 Sept on wards I wish to visit other places of Japan such as Kyoto, Hiroshima, Osaka terminating my trip at Kagoshima with two nights' stay there.
I plan to leave Kagoshima on 9th Oct late evening so as to reach Tokyo next morning and then proceed to Narita. I wish to take Sunrise Ltd Express sleeper train overnight journey from Kagoshima to Tokyo. I want to do all my trips including the last one by using JR pass.
Now my question is does it sound like a good itinerary or it can be improvised? I also request you to guide me about other possible stops on my onward movement from Tokyo to Kagoshima.

From Narita into Tokyo you can use the special 1500 yen Narita Express (NEX) ticket.

You will need a 14-day JR Pass, starting on the 27th. I would take the Shinkansen to Hiroshima the first day, then go on to Kagoshima, then come back to Osaka and Kyoto.

On your last day, you can take the Shinkansen from Kyoto to SHINAGAWA station in Tokyo, then change to the NEX to go out to Narita.

In Tokyo, I would find a hotel near SHINAGAWA station. SHINAGAWA is not as large as Tokyo, and you can get anywhere around the city easily using the JR Yamanote Loop Line. There are many hotels there and access to the subways via the Keikyu private railway.

Thanks Dick for your nice suggestion. While your Hiroshima through to Kyoto is most exciting I am worried about one thing. You suggest that I start my journey to Hiroshima on 27th with the 14-day JR Pass. Where do I spend the 26th night when I land in Tokyo? Do you propose me to stay overnight at a hotel just to wait for the Hiroshima journey next day?

I don't think your plans for train travel from Kagoshima to Tokyo on your last night will work. Read more about night trains in Japan here:
http://www.japan-guide.com/e/e2356.html
Generally speaking, night trains are not a very good option for travelers with a rail pass because you cannot be sure of getting a reservation. (And, the rail pass doesn't cover sleeper compartment charges, and the floor spaces that are fully covered are notoriously uncomfortable for sleeping.) Better to take the shinkansen as suggested by Dick H. Kagoshima is kind of a distant destination for a 15-day itinerary, although it's certainly possible.

As stated above, I would not travel to Kagoshima straight to Tokyo, but I'd do Tokyo - Kagoshima and then work my way up. I'd also recommend spending a day in Fukuoka.
Maybe even, to not having to make amazingly long distances at once you could do Tokyo - Hiroshima - Kagoshima - Fukuoka - Osaka/Kyoto - Tokyo, therefore you wouldn't be making very long trips at once which can be tiring and you wouldn't loose a full day travelling but smaller portions of time distributed in several days which can be more convenient. You could even depart Kyoto or Osaka for Narita on your final day.

Thanks everyone for such useful tips. I now feel doing the small trips is more worthwhile as I can use the hours between checkout from the previous hotel and check in to the new hotel for travelling.

Are the travels you all have suggested be done between 1000 hrs to 1600 hrs?

Please help.

"You suggest that I start my journey to Hiroshima on 27th with the 14-day JR Pass. Where do I spend the 26th night when I land in Tokyo?"
I did NOT say that. I said to activate the pass on the 27th. YOU said you will stay in Tokyo for 4 nights, did you not?
That will be the 26th, 27th, 28th and 29th. Then you start your long trip on the 30th.

Thank you Dick H for the clarification. I understand now.