Your spec for 80 is vile.
If you're a PVE player, I recommend deep fire or frostfire. Arcane is generally fine too if played well. Rarely can a frost mage pull off sufficient enough damage in PVE situations.
However, if you're a PVP player, frost is the favorable PVP spec. If you're willing to take PVP as a mage further, and deal with more complex confronations, arcane is a more advanced yet effective spec.