The best kept secret of seating on A320 is row 17. Rows 17 and before are blocked for P/E/SE, and of course, 12 (first row) and 15/16 (emergency exit rows) are assigned at airport. Which means only 13, 14 and 17 can be reserved at booking. For some reason, everybody goes for 13 and 14 with less legroom. Go for 17.