Default to a larger font size.
Many websites out there have very little regard for the disabilities that their customers face. By our very nature, our customers or viewers have more disabilities that the average Joe Bloggs.
May I suggest that the default settings for any post be set to a largish font? People tend to just use default rather than what’s most easy to read. Black on white may not be the best colour either for some folk.
Anyway, just a suggestion.