After converting several bikes to ebikes from kits, it takes a lot of trial and error to get braking right. Obviously one of the most difficult and important parts of the bike is braking. I've tried different types of discs, pads as well as wired and hydraulic systems. And I agree with others posts here, higher quality pads with disc brakes make a big difference, but hydraulic systems are by far the best option for more stopping power. Most motorcycles use hydraulic systems for a reason and in my opinion ebikes are much closer to a motorcycle than a bike.