[kq76]

It is possible. I'm working on a skin right now.

Go to File > Workshop Central > Open Workshop. That will open up Steam. Find the skin you want to change, click on it, then click "+ Subscribe". It might take awhile to download. Find your data/skins folder, open the subfolder of the skin you downloaded and delete the skin.bin file. Go to File > Workshop Central, click on the skin you want to change and then click on "This item is downloaded... re-install it". Then once it's done, go back to the skin folder and start changing things.

The defaults.cfg file does have some font stuff in it. And colours/colours.cfg has colours in it, but it's not well documented what each line does so you'll just have to test each color code and then try to match it to what you see in the game.

Unfortunately from there you're on your own as I'm just now learning this stuff too.

EDIT: You could try the other fonts available via Settings on the start screen, but re-reading your post it sounds like what you want to do is edit 1 or both of those cfg files.