Why the preference for exclusively serif fonts? Maybe add the option of choosing between a small set of fonts?
Sans-serif fonts are better for those of us with dyslexia (overall base rates are ~20%). For specific suggestions, Roboto (open source with an Adobe license) or Proxima Nova are clean and inclusive.
I was just looking into this and found another resource tracking donations. It stops in 2023 but maybe I can get a PR accepted that extends this to the present.
https://donations.vipulnaik.com/?cause_area_filter=AI+safety