what are u planning to do with this spec?? PvP or PvE?
if PvE: why "Improved CS", "Arcane Fortitude", "Blast Wave"? i would skip them for "Empowered Arcane Missiles" and "Arcane Impact" if your going the PvE way.
if PvP: i would put the 3 points of "Improved Scorch" into "Improved FireBlast".