Hakone - bullet train and plans

Hi, I am planning a 1-day trip to Hakone from Tokyo.

(1) I would like to experience a one-way bullet train ride. Which one is better from a tourist point of view, going or returning journey?

(2) For just a single trip, can I buy the ticket at the station or do I need to make a reservation online (like airline ticket)? What are the chances that there will be no seats on a weekday?

(3) If I dont intend to do the full round course, is it still possible to experience the onsen, black egg, lake ashi and cable car?

Thank you

(1) I would like to experience a one-way bullet train ride. Which one is better from a tourist point of view, going or returning journey?

I would do it going there, as it makes the journey there quicker. Tokyo - Odawara, or Shinagawa - Odawara. Try and go from Tokyo as that gives you more time on the Shinkansen.

You may also decide that you enjoy it so much you wish to do it for the return journey I guess.

(2) For just a single trip, can I buy the ticket at the station or do I need to make a reservation online (like airline ticket)?

You can't buy it online so you should do so at the ticket office at the station.

What are the chances that there will be no seats on a weekday?

Probably rare that there will be no seats available. Even if there are none available to reserve you can always get a non-reserved ticket and try and get a seat in the non-reserved carriages by queueing up.
Shinkansen
http://www.japan-guide.com/e/e2018.html

(3) If I dont intend to do the full round course, is it still possible to experience the onsen, black egg, lake ashi and cable car?

Yes, but that sounds like most of the round course so I'd probably just do the round course.
http://www.japan-guide.com/e/e5210.html

Enjoy your trip!

Hello, thank you for a detailed reply. Cheers

Hello, me again =)

Hi, if I purchase the Hakone Freepass at Odawara Station (3900 yen), can I use it for the Hakone Tozan Railway to Hakone-Yumato?

I ask this because the Freepass price is the same regardless whether it is purchase from Odawara or Hakone-Yumato:

Thank you

if I purchase the Hakone Freepass at Odawara Station (3900 yen), can I use it for the Hakone Tozan Railway to Hakone-Yumato?

Yes.