serif vs sans serif is not "a vague aesthetic reason", it's the most fundamental typeface choice you can make, moreso than monospace (which is an artifact of some 19th century technology) Rubio is an attorney, and there are many stylistic conventions in the legal and judicial space, why ruffle those feathers by flouting them? if you are given a style guide for your PhD thesis, do you follow it or do you futz endlessly with the fonts to show them what an independent thinker you are?