I don't have a full day to devote to Hakone. Just isn't there. But would really like to go--I love volcanic features--and am wondering if I can shoe-horn it in. The two things I'd most like to do are:

1. See the volcanic area (where they sell the boiled eggs)
2. Experience a private onsen (wife & I aren't doing the gender-segregated thing)

How many minimum hours would I need to allocate for that? And if goal #1 is implausible, are there other cool spots along the way that would make the journey worthwhile? I know there are various funiculars and "rope ways" that sound fun. Don't care about the "pirate ship."

I have one overnight in Kyoto. Trying to maximize my time there. If I wasn't thinking of Hakone I'd try to do two full days in Kyoto. But I'm willing to sacrifice half a day. Here's what I see as my options:

A. Stop in Hakone on my way from Shinigawa Station to Kyoto
B. Stop in Hakone on my way from Kyoto back to Tokyo (Hilton Tokyo Bay)
C. Visit Hakone in the morning from Hilton Tokyo Bay Hotel. Flight out of NRT @ 7pm.

If any of these options are plausible at all, which is more plausible and why? I'm leaning toward B since Kyoto is the priority destination. I don't mind arriving back in Tokyo late. May use a luggage forwarding service. Option C gives me the willies a bit, as I don't like doing day trips with lots of transport connections on the day I fly out of a foreign, new-to-me city. But I'm putting it out there anyway.