JR Rail Pass?

I was wondering if the 21 day rail pass is the best value for our plans:

April
26 arrive in Fukuoka
27 to Kagoshima
28 to Yakushima
29- May 1 Yakushima (to see the Yaku-sugi)
May 1 travel to Beppu
2 stay in Beppu
3 to Matsuyama (via ferry)
4- 5 Matsuyama and around
5 travel to Takamatsu (for the gardens) then on to Hiroshima
6- 8 Hiroshima and around
8-9 travel to Yonago and Misasa
late on the 9th to Kyoto
10- 12 Kyoto
12- 14 Mt Fuji and around
14 to Tokyo
15- 18 Tokyo
19 go to the airport

We are staying longer than 21 days, but we are staying on Yakushima for a bit, so we could activate later...or opt for a 14 day and pay out of pocket for the trip down to Kagoshima. I don't know! Thanks for any help you can provide :-)

Colleen you will find all the fares at
http://www.hyperdia.com/ you might find the "classic version" easier to use and make sure that you tick Nozomi out of the equation.
By using that you can best work out your ticketing arrangements.

Keep in mind that besides the cost savings it gives you also a lot flexibility. Especially if you do not speak Japanese. You just hop on an JR train (and some busses) without bordering that you have the right ticket (do not jump into a green car unless you have a green car railpass and do not jump on a Nozomi bullittrain).
And in big cities it even gives you the possibility of a shortcut through a station rather than walking around a big station.
B. Slager