I used the app and tuned all the levels to their max setting. Then I ride in L2 or L3 pretty much everywhere. I only ever go to L5 for short pinch climbs.
Just watch the cable bend out the bottom of the seat tube. I found once the motor is installed again, it locks the cable in place so I had to get the length of the seatpost right first.
I recently discovered Beau Miles. While technically not about riding, he does some pretty interesting endurance stuff like walking his 90km commute to work and having to sleep and eat with whatever he can find.
I'm surprised there hasn't been a frame come out with a universal mount system that used adapter inserts for the different motors e.g. take a motor, bolt the adapter to it and then bolt that into the frame. That would make pivoting to a different motor trivial for a manufacturer since they'd...
I would drop the existing motor and have the donor alongside. Unplug and move each cable one at a time and you shouldn't get it mixed up. Then power and test it starts up before bolting it all back together.
I turn the power up when I go downhill because if I have to pedal it's because I need the help i.e. didn't go into a feature with enough speed etc. The rest of the time I'm not pedaling so it's not using any more power.