Typeface matters. If I can't read it comfortably, I won't read it. I have a pile of candidates and only limited time to review them.

The rest of your points are succinct and absolutely true - I just wouldn't write off the importance of the font. By sticking to your advice: "most common fonts are fine" people should avoid the rubbish font trap though

Sorry - I'm maybe being a little nit-pickey there.