Brake pedals always get better after a few miles as the initial profile of the pads/shoes never matches the discs/drums at first. After a bit, they do, so the pedal improves.

Don't know if this applies to the current three wheeler since the car width rear tyre will be a bit more stable than a bike tyre; rear wheel lockup is a recipe for disaster. I've locked the back wheel at less than 30 mph on a vintage trike and you need new trousers and underpants...

1930 Super Sports Aero 'The Elk'