help with mage build?

I didnt get the game yet cause of bloody itech but hopefully i can withing the coming week at the time being i was browsing the ign talent generator and experimented with it a bit i founda build i like but i run short of 3 points which i wanted in improved flamestrike .
the build looks something like this by 60:


28Arcane/23 Fire i was wondering how would you recomend to go investing into talents as you level since we obviously dont start at level 60 IF i ever get my hands on the game.


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Arcane Talents (28 points)


Improved Arcane Missiles - 5/5 points
Gives you a 100% chance to avoid interruption caused by damage while channeling Arcane Missiles.


Arcane Concentration - 5/5 points
Gives you a 10% chance of entering a Clearcasting state after any damage spell hits a target. The Clearcasting state reduces the mana cost of your next damage spell by 100%.


Evocation - 1/1 point
While channeling this spell, your mana regeneration is active and increased by 1500%. Lasts 8 seconds.


Improved Arcane Explosion - 5/5 points
Reduces the casting time of your Arcane Explosion by 1.5 seconds.


Improved Dampen Magic - 2/2 points
Increases the effect of your Dampen Magic spell by 50%.


Improved Counterspell - 2/2 points
Gives your Counterspell a 100% chance to silence the target for 4 seconds.


Arcane Meditation - 4/5 points
Allows 12% of your Mana regeneration to continue while casting.


Presence of Mind - 1/1 point
When activated, your next Mage spell with a casting time less than 10 seconds becomes an instant cast spell.


Arcane Instability - 3/3 points
Increases your spell damage and critical strike chance by 3%.



Frost Talents (0 points)


None

Fire Talents (23 points)


Impact - 5/5 points
Gives your fire spells a 10% chance to stun the taget for 2 seconds.


Improved Fireball - 5/5 points
Reduces the casting time of your Fireball by 0.5 seconds.


Ignite - 5/5 points
Your critical strikes from fire damage spells cause the target to burn for an additional 40% of your spell's damage over 4 seconds.


Flame Throwing - 2/2 points
Increases the range of your fire spells by 6 yards.


Pyroblast - 1/1 point
Hurls an immense fiery boulder that causes 148 to 195 fire damage and an additional 56 damage over 12 seconds.


Incinerate - 2/2 points
Increases the critical strike chance of your Fire Blast and Scorch spells by 4%.


Critical Mass - 3/3 points
Increases the critical strike chance of your fire spells by 6%.

Grab your first 16 points in arcane first - imp missiles, arcane med, evoc, imp arcane explosion. From there it's up to you. ;)

hm i cant decide whether to get criticall mass or improved flamestrike? imp fs give like +20% crit chance on flamestrike and critical mass 6% crit chance on all spells

Critcal mass imo - flamestrike is rather situational.