If you have all Astral Fire and Umbral Ice stacks ready, you can combo 2 Fire II casts followed by 2 Flare casts (i usually keep swiftcast for the double flare) for some great AoE dmg, bonus points if you also use sharpcast beforehand for thunder IV, but that combo is mainly used on large Dungeon pulls, since Fire II is in my book only worth using when you fight 4 or more enemies at once.

Now Blizzard II and whatever the hell Scathe is suppoest to be, deserve some serious attention for a rework. I'd be glad if Ice II would get its root effect back so that it would be at least useful in PotD and HoH.