Just a few pointers from E.P.

• No low x-heights (Apercu is a good example, while Futura is not).
• Pair complementary typefaces (serif with sans serif not serif with serif).
• Aperatures (partially closed negative space), counters (closed negative space), and eyes (‘e’) need to be large enough (eyes vs. counters).
• Look out for serifs, links (connecting bit ‘g’), ears (‘g’ and ‘n’ tabs), and spurs (pointy bits on letters ‘G’).
• AVOID Helvetica, especially Neue.