This is a perfectly achievable trip.
These days, there are plenty of QC charging opportunities between SF and San Jose/Los Gatos.
On the last leg of your trip from Los Gatos to Santa Cruz, I recommend driving to the summit on highway 17 at the 55 speed limit or less, and once at the summit, exiting highway 17 onto Summit Rd south to Old San Jose Rd. into Capitola then to Santa Cruz.
Old San Jose Rd is a rather steep downhill drive, and because of that you will recover about 85% of the energy expended getting up to the top of the Highway 17 Summit. In addition this is a lightly traveled road, so you can essentially regen all the way down without having to use the brakes, and still keep the speed limit.
Old San Jose Rd. is also very scenic, and is only marginally longer than driving down Highway 17.
When I drive this route, but the time I get to the Highway Summit, I am down to 5~6 bars, but by the time I get to Capitola, I am back to 10~11 bars.
This is a perfect example of where gravity is your friend.