18 Day Itineray Help

My husband and I will be traveling Oct 26-Nov 12. I would greatly appreciate any thoughts on the below itinerary (overnights locations are in parentheses). We currently plan to get a 21-day train pass. I am open to all feedback!

1 - Arr 4pm Narita (Tokyo)
2 - Tokyo (Tokyo)
3 - Tokyo (Tokyo)
4 - Nikko (Nikko)*is this better as a day trip from Tokyo?
5 - Kamakura (Hakone)
6 - Hakone (Hakone)
7 - Fuji/5 lakes (Kawaguchi)
8 - Matsumoto/Takayama (Takayama)
9 - Takayama (Takayama)
10 - Kanazawa (Kanazawa)
11 - Hiroshima/Miyajima (Miyajima)
12 - Hiroshima/Himeji (Kyoto)
13 - Kyoto (Kyoto)
14 - Kyoto (Kyoto)
15 - Kyoto (Kyoto)
16 - Nara/Koyasan (Koyasan)
17 - Koyasan (Tokyo)
18 - Lv 7pm Narita

Thanks so much!

My thoughts:
day 4 Nikko as a day trip from (Tokyo) Why to bother with the luggage just for one night.
day 5 Kamakura as a day trip from (Tokyo). Otherwise with luggage by local train to Kamakura, with luggage to Great Buddha, with luggage to Fujisawa change train to local train to Odawara, change train to Hakone-Yumoto. Arrival too late for Hakone tour.
day 6 Even this I recommend as day tour from (Tokyo): in the morning by Kodama shinkansen to Odawara then Hakone weekday pass make the round and evening back to Tokyo by shinkansen
day 7 Make it a day tour from (Tokyo), too. For tomorrow you must return to Tokyo anyhow
day 8 There is no direct JR train between Matsumoto and Takayama. So your plan means: Tokyo - Matsumoto 3 hours train - sightseeing - 5 hours train down to near Nagoya ( Tajimi ) and back up again the other line to Takayama. If it MUST be ( the castle of ) Matsumoto, even this as a day trip from (Tokyo)
day 9 Tokyo shinkansen Nagoya - express - (Takayama)
day 10 Takayama - Kanazawa has bad train connection, but can be reached by a direct express train from Kyoto ( 2 hours ) so: dep morning Takayama express Nagoya shikansen early afternoon arrival, sightseeing and overnight (Hiroshima)
day 11 as mentioned
day 12 morning Hiroshima shinkansen Himeji 2 hours castle Himeji 12.02 h shinkansen Kyoto express ( Kanazawa ) 15.21 h arrival sightseeing garden
day 13 morning Kanazawa - (Kyoto)
day 14 to day 18 as mentioned