Haven't stayed at Gora Kadan but have taken the old train between Gora and Hakone Yumoto several times and not only never had it crowded, I found it charming. They have to reverse direction (and the end of the train which is the front) three times along the 40 minute trip.

Y33,000 for a taxi between Gora Kadan and Hakone-Yumoto is absurd, I hope that the OP means Y3,300. By comparison, the train fare is Y400.

Assuming that the taxi fare listed above is wrong, it would be significantly more efficient to take the taxi a bit further, directly to Odawara station. Some other Gora hotels provide a limited free shuttle service between the hotel and Odawara station and v.v.; it might be worth investigating if the Gora Kadan does as well.