The major parts have arrived and been tested. Found that the wireless charging module and coil get really hot (starts to soften the 3D-printed wall plate). 

Now I need to think of a clean way to manage this heat but I can't put a heatsink on the coil because the motor shaft needs to go through it (a potential solution is to get some round aluminium blanks with holes in the middle and have thermal pads in between). The controller board can just have a heatsink installed on it and hopefully, convection can keep them both cool enough.

The coil or PCB is whining sometimes at the start and end of charging (when the tablet is removed from the coil) but I dont think it will be that audible when it's all closed off and in the wall. The good news is that the tablet is able to charge while being 8 mm away from the coil, I did wonder if the distance was causing the coil to heat up but I used a thermocouple probe on the coil when it's directly under the tablet and it still heats up so that rules the distance idea out, I may try out running the charger at 5/9v which reduces the wattage of the charger and so should reduce heat but I still want to be sure the module won't destroy itself at 12V.