Is this to make space for the display or is this the recommended way in general?
Coming from the Raspberry Pi, I would have looked at taking 5V from the 40-pin-connector. Would that work in general?
I have been implementing Soft PWM for the other GPIO pins to be able to use more standard RPi boards, so power supply seems to be one of the larger question marks.
You can draw 5V from the GPIO pins. That rail seems to be less protected than USB, though – each USB port seems to be connected through a load switch that will turn off on over-current, if I read the schematic right.
In general, though, it’s not a great idea to draw motor power from either of those, at least not without additional filtering – a 100 uF or 470 uF capacitor would be a good start.
So I am trying to use Pi-HATs directly ( https://github.com/pimoroni/explorer-hat ), but so while it appears to work reasonably well, it is not to be used without caution.