I am very easy going, amenable guy. Far be it from me to niggle about grammatical stuff. I’m happy that people still write at all anymore. But that said, these are two punctuation peeves that eat away at the fabric of my psyche:
Using quotation marks for emphasis. Use quotation marks for, well, quotes. If you want to emphasize something, use italics or bold case. Quotation marks do not make the text you are reading seem “more important.”
Using an apostrophe before a plural ’s’. Apostrophe’s are for possessives, not plurals.
Of course, confusion over when to use ‘which’ and ‘that’ is totally understandable.