Yes, you could probably do a day trip to Kamakura, but you'd have less backtracking if you got off at Yokohama, took a subway to Shin-Yokohama, and caught the Shinkansen there.

I don't know if you've looked at a map of Kyoto, but Fushimi is what passes for suburban in Japan, a bit out of the way for sightseeing except for the Fushimi Inari Shrine and Uji. You'd be better off with something near or north of Kyoto Station if you want to concentrate on the main sights of Kyoto proper. There are entire guidebooks for Kyoto, so I suggest getting one.