Fine details blur less, or at least more slowly, with ink around them. So might be a good idea to have a halo of white or some other color around the letters, or perhaps have them all in a tasteful frame of a more subdued color. I also agree with the other comment that you may want to save up to have an experienced artist do the piece; a more practiced hand will get the lines crisper and do less damage, which will help them stay better longer.
There is a Thinkpad (x12) that has a detachable keyboard. Thinkpads usually play nice with Linux, but I can’t speak to that model specifically.