I was just thinking what skills the hybrid character I plan to make should take. I started comparing two contenders for a ranged area attack. The best choices would be Fire Ball or Exploding Arrow. It's probably not a good idea to take both considering how similar they are. Here's the stats of both, comment or even list any skills you have trouble choosing between.
Fire Ball- Maxes out at Rank 14
Base Damage: 1592
Base Mana Cost: 100
Damage Range: 12 Ft.
Side Effect: 18% chance of Burn damage(how much damage does this do?)
Cooldown: 15s
Comments: The spell will cost 50 with a rank 5 Mana Efficiency. Unlike EA its damage can be boosted to very high levels. Intelligence can give it up to a 100% boost, Destruction can boost it another 50%, and Way of the Battle Mage can add another 60%. So It's Maximum Damage is 1592*2*1.5*1.6=7641.6. Rounded that's 7,642 over a 12 foot range with a 18% chance of inflicting extra burn damage. All that for 50 mana every 15 seconds.
Exploding Arrow- Maxes out at Rank 13
Base Damage: 2014
Base Mana Cost: 62
Damage Range: 17 Ft.
Side Effect: 34% chance of Knock Down
Cooldown: 5s
Comments: Costs 31 with a rank 5 Mana Efficiency. It's base damage is higher than FB, but it can't be boosted. It's also cheaper and can be used more often over a larger area with a potentially better effect.
Summary: FB can be learned from the beginning of the game and does not require a bow to use. You could even use it with weapons drawn or sheathed. However it requires more work to get to that 7600 damage mark. EA only needs 13 points while FB would require 24 to reach that high damage. Unless your a battle mage or just a pure mage that would require too much investment to boost the power of one skill. So EA is the best skill for a hybrid character.