3 nights trip out of Tokyo

Planning 3 nights away from Tokyo. I was looking at a night in Kusatsu Onsen then 2 other nights somewhere else. Thought of Oigami Onsen as the waterfall is so beautiful but it is also time consuming traveling between the two! What a pity there isn't a bus route along Japan Romantic Road.. :-(
I'm running out of time to research and book for a new destination near Tokyo. My trip is end of March and the intended 3 nights away Apr 1-4.
Which other Onsen villages aside from Kusatsu has nice ambience, with some nearby attractions and is not so complicated to get to from Kusatsu? I don't want remote places where there is nothing to see aside from onsen bathing. It will be great if I can get suggestions for an itinery for 3 locations which are relatively easy access to each other and not too far from Tokyo. Been to Nikko and Chuzenji so not there.

Have you been to Kamakura, Fujisawa, Ennoshima area? Pretty close to Tokyo and lots of history (temples and such), beauitful coastline, and some good food!