I'm age 69 & when I take a downhill tight curve at 30 mph, a 3 wheel would fall right over and scrape my arm leg and maybe helmet all the way until we stopped. 3 wheels are for grandma's at 6 mph around the retirement community. Or people with a heart condition or inner ear problems. I'm 8 mph average on the level w/o power but I take full advantage of any down hills if the pavement is dry.
BTW, my bike weighs 94 lb with battery, motor, rack, full set of tools to allow repair off the cell phone grid. I have no trouble handling it. You'll see I have my battery out on the front over the wheel, to balance the loads in the back. Also keeps any possible battery fires away from my crotch.
Note to OP, I live in a hilly area, and my bike has 3 front speeds & 8 back. I pedal unpowered with a geared hub motor unless the wind is >12 mph in my face. Keeps the heart pumping. No drag from a geared hub motor.