We leave in a week and have our order for a JR pass. Yes I know to convert it when I get there. Question. Should we make reservations for our seats from Tokyo to Hakone and from Hakone to Kyoto and Kyoto to Osaka airport right away when we get there or are seats usually available?

Is that your entire JR itinerary? Tokyo to Odawara (JR doesn't exactly go to Hakone), from Odawara to Kyoto and from Kyoto to Kansai Airport? If that is all that you are doing then you don't need a JR Pass. Same would apply if you meant Osaka Itami Airport.

When you exchange the voucher for the pass then you could get your reserved seats at that time if you want.

The trip from Tokyo to Odawara is short so that if you didn't have a reserved seat you would be okay. The train originates at Tokyo so the unreserved shinkansen cars would be empty when boarded there. You can take a Hikari or Kodama shinkansen.

From Odawara to Kyoto I would want to get reserved seats in advance, at least a day or two before. Most seats are going to be reserved from Tokyo or Shin Yokohama - before Odawara.

Check the schedule closely for Odawara to Kyoto and make sue that you get on a Hikari shinkansen. You don't want to take a Kodama shinkansen for that trip, they are too slow (in some cases it would be better to back track to Shin Yokohama to catch a Hikari from there that passes thru Odawara - not all Hikari stop at Odawara).

For the airport trip reserve the seat in advance since your departure time is fixed by your flight time.

3840 from Tokyo to Odawara on Kodama shinkansen
12150 from Odawara to Kyoto on Kodama/Nozomi
3700 from Kyoto to KIX on Haruka ltd exp

That's just under 20,000 yen vs 28,300 for the 7-day JR Pass.

We are also planning on going to Hiroshima and possibly Nara. We should come out with the pass, but really not that big a savings. Initially we thought we'd have to go back to Tokyo, but we are now flying out of Osaka which saves us time.

To Hiroshima and back is 22,000 so you would be saving a decent about 14,000 if you used a 7-day pass. But you must have vouchers for 14-day passes. ? In that case, that's 45,100 and you would break even if you took all of the travel mentioned before and used it to get from Narita Airport to Tokyo. You'd get a savings of the Nara roundtrip with the pass.

But by purchasing individual tickets you could offset that by not taking the shinkansen to Odawara. You could use the Odakyu train to go from Shinjuku to Odawara.

Close to break even like that I would buy individual tickets for the convenience of the Nozomi shinkansen nonstop to/from Hiroshima and to open up more options from Odawara to Kyoto.

But the use of the pass is very convenient and it gives you a lot of flexibility.

pass is convenient. even if reserved seats are not available, there are always non-reserved cars where if u arrive early and are first in line you are there. we only ended up once in a smoking car w/o reservations, but we ran onto the train last minute

even if you don't have enough time to get to hiroshima from kyoto, definitely go to Himeji to see the castle for 1/2 a day ... that will make your JR Pass pay out AND you get to see the BEST feudal castle in Japan