JR Pass or rather book normal in Obon week (and costs?)

Hi all,
I wanted to know your opinion if a JR Pass actually makes sense (or not at all) for our JP trip in August.

Data:
- 2 adults - 2 kids (13/8 years) - from 10th August to 6th September

The planned stops are:
- 10th to 12th August Tokyo - 12th August to 17th August Kyoto (*) - 17th to 22cnd August Osaka a) Himeji
b) Kobe
c) Hiroshima incl. Miyajima via ferry
d) Nara
- 22 to 23rd Hakone - 23rd to 6th Tokyo at a place where there is no JR line sadly maybe some minitrips from there

(*) due to Obon we need secure transport to Kyoto but with JR pass we can't reserve right? Which made it "problematic in my point of view" vs. booking it in advance to normal rates. Is there an option to reserve already your trip if the pass is active only as of 12th August?

I used the JR calculator but even "only" taking the 14 day pass I'm still around 65€uro (10464 JPY) behind break even. Of course I missed out some local mini-trips (Kyoto/Tokyo) but mostly the rest is included. 21 days makes the whole calculation even worse. Combined with the Obon week challenge (we must have secure transport) it seems the regular JR Pass sadly isn't the best choice this time.

I thought about buying the JR West Kansai-Hiroshima Area pass for 5 days and combine the trips from Osaka (Hiroshima/etc) inside the 5 days and otherwise take normal tickets and a Welcome Suica.

What are your thoughts here?