I had an electric winch for a few years and it worked well, the only problem was I was using crocodile clips on the car battery. This meant I had to have the bonnet up and cable lying on the ramp. It was a messy solution so if you go electric work out your power supply first. This might entail having to run some power cable to a socket at the back of your car.
Today I put the trailer in deeper and drive the boat onto the traile and one or two winds completes the process.