jks

Just about any 30x30mm brushless 3.3-5V fan will do. Try to get one with ball instead of sleeve bearings. Running a 5V fan on the 3.3V from the Kiwi Grove connector is fine and will reduce the fan noise (I believe the enclosure ships with a 5V fan).

When the time comes the biggest problem will be putting the Grove connector on the new fan leads. The pins should be removable from the white body of the Grove connector. Or you could cut-and-splice the wiring. I prototyped with some fans from Mouser I think.

v1.291  June 13, 2019
    Fix problems with the last release:
        Deleting masked frequency labels.
        Missing echoing of black dots in password fields.
        A single step of the mouse wheel didn't always zoom.
        Reduce unnecessary cases of "click to start" being displayed.

With a TVS it's not so much the voltage that kills them as the time profile of the current pulse. The Kiwi uses the CDSOD323-T03C and the data sheet is here: https://www.bourns.com/docs/Product-Datasheets/CDSOD323-TxxC.pdf

Okay, this was relatively easy and will be in the next release.

That will work fine. I do it here.