Revision 2.0 is here! It involves a new layout for the GPS module, with the top layer being the primary ground layer. This should improve the GPS signal because it gives a larger ground plane for the built-in antenna. I also added some user configuration on the bottom, where the user can close jumper pins to connect certain GPS output pins (INT, PPS, ~RESET, ~SAFE) to prechoosen Feather pins. The new .GBR files and KiCad Design Files will be uploaded to Hackaday shortly.
Below are some photos of the traces and KiCad renderings of the board.