Hi there!
I think your plans are good, assuming that there are no daytrips. The difference between a 7 and 14 day JR Pass is ¥16,800, so your extra trips would need to exceed this for a 14 day pass to be worthwhile. If you do day-trips to Nikko and Hakone/Odawara your costs would look like:
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Tokyo > Kyoto: ¥13,420 (164mins, 513km)
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Kyoto > Osaka: ¥540 (28mins, 42km)
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Osaka > Hiroshima: ¥10,150 (104mins, 345km)
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Hiroshima > Kyoto: ¥10,990 (126mins, 380km)
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Kyoto > Nara: ¥690 (44mins, 41km)
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Nara > Kyoto: ¥690 (44mins, 41km)
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Kyoto > Tokyo: ¥13,420 (161mins, 513km)
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Tokyo > Nikko: ¥5,630 (121mins, 150km)
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Nikko > Tokyo: ¥5,630 (117mins, 150km)
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Tokyo > Odawara: ¥3,840 (35mins, 83km)
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Odawara > Tokyo: ¥1,450 (36mins, 83km)
JR ticket cost: ¥66,450 for 11 legs
As you can see you'd make savings with both 7 and 14 day options. Your extra day trips from Tokyo add up to ¥16,550, which is basically the difference between a 7 and 14 day pass. Because of this , if you intend to do these day trips I recommend the 14 day pass as you'll also be able to do the return to Narita on the Narita Express plus have free JR travel within Tokyo (further savings of ¥3000 to Narita plus around ¥500-¥1000/day savings on JR travel within Tokyo).
If you don't do the daytrips, I recommend you use a 7 day pass for your travel outside Tokyo as you plan, and then use either the [Keisei Skyliner + Metro pass], or [Narita Express + Suica deals] to get you to and from Narita + discounted travel within Tokyo, in addition to some 2 day metro passes to fill in the gaps (you may also find the metro passes useful if you choose a 14 day pass).
You can look up precise train timetables and costs at the Hyperdia travel planning website and learn how to use Hyperdia for JR Pass holders through our video blog.
Hope this helps!