score:6
From Tokyo, you've got two choices:
To Osaka, life gets more complicated:
I rarely recommend rental cars in Japan, but the Fuji Five Lakes is one of the few areas on Honshu where it makes sense. Don't rent from Tokyo, though, but at a suitable station along the way; then if heading towards Osaka, you could drive around Fuji and drop off the car at (eg.) Shin-Fuji stn before continuing by Shinkansen.