Hi Christina!
From your itinerary it looks like you are planning on a 17 day trip - am I correct in this? As you'll spend 7 days in Tokyo in total it is unlikely you'll need a rail pass for this part of your trip. Lets take a look at your costs of your trip for the 10 days from when you leave Tokyo to when you get back. For a 14 day pass to be worth it for this part of your trip you'll need to spend over ¥45,100 on individual JR tickets.
- Tokyo > Kisofukushima: ¥11000, (206mins, 340km)
- Kisofukushima > Nagiso: ¥570, (35mins, 34km)
- Nagiso > Kyoto: ¥7230, (152mins, 246km)
- Kyoto > Osaka: ¥1680, (27mins, 42km)
- Osaka > Tokyo: ¥13750, (194mins, 556km)
TOTAL: ¥34230 for 5 legs
As you can see, from base costs alone it will be most economical to purchase individual tickets rather than a 14 day rail pass based on your current itinerary. A 7 day rail pass at ¥28,300 also doesn't look like it would fit given your plans.
If you did purchase a 14 day rail pass you would have an extra 4 days of free travel on JR transport - if you made the most of this, it would be possible to build up your travel costs to make a 14 day rail pass economical, but this really depends on the flexibility of your plans. You can find some options for good day trips from Tokyo here.
Hope this helps!