After playing a bit this morning and looking through the chars, it seems that Dark Forces really have a big early game advantage over light. I am not sure if this is intended, however as a light player it seems an uphill struggle for the first 5 levels.
You generally have to hope that you don't let dark get too far ahead, and once you are strong enough you can claw back the game.
Just looking at the abilities and from playing the chars a bit, dark gets some really useful big abilities at the start of the game :
UB - Spit (awesome skill, most damage, ranged)
Erebus - Bite (killer skill you cant get away if you get caught)
TB - Fireball (decent damage, most probably weakest for dark)
QoT - Bramble shield (can cast at start, then recast once worn off, effective 1400Hp at start!)
All of these core level 1 skills are bread and butter and work great early game.
For Light it is not so useful, most of the core skills are not immediately beneficial.
Reg - Mines (useless at start powerful at end, have to hope you can hit the enemy DG or be in close, see snipe!), Snipe (high cost and low damage up close, where you WILL die as Reg).
Sedna - Heal (most useful for Light, but not as powerful as bramble shield, prevention better than cure as they say)
Rook - Towers (useful for holding areas, but means rook has to be stationary), Hammer Strike (only good for creeps)
Oak - Penitence (low damage)
I think that Spit and Bite need to be scaled down a little early game. It seems that only one Light DG can really hold an area early game, that being Rook, the rest have to spend their time harassing until they can level up. Usually meaning no flag control or lack of creeps. Once past level 5 it really balances out again, but in Pantheon it is tough as early game for light seems to be most spent running back to towers.