viewtopic.php?f=5&t=58269 also contains information about the 90 cap build.
My advice for the 90 cap:
90 bicheon / 90 lightning / 60-90 cold / 30-60 fire
90 force / 90 lightning / 60-90 cold / 30-60 fire
90 fire / 90 lightning / 90 cold
Alternatively, if you don't mind deleveling fire later or if you don't plan on playing when the cap increases again:
90 bicheon / 90 fire / 60 cold / 60 lightning