I really like the mull.in keymap and flash it on any keyboard I am using, so here is a repo with a keymap for some keyboards in QMK.
To use these keymaps just copy the folder with the name of the keyboard you are using and paste it under the keymaps folder for that keyboard.
Example: qmk_firmware/keyboards/"YOUR_KEYBOARD"/keymaps
Here are images from mull.in on what his keymap is:
