Elemental Equilibrium Bow Scion of DOOM

I am going to start building an EE Scion Archer.

Here is the skill tree I am going to be working with...

http://www.pathofexile.com/passive-skill-tree/AAAAAgAB8pebXaiaWlJJZ5ARguRKyD8nKk0VICzpytMZtPqx6mLexs2YjX63tr6n0k3AD9Xt6yySzaxHkvMZhspKwzqbtVM1bWy1SCpb1tHSGW17VUsmlYw2pLHljghnkzq9Jxg8-eiCxyj6mK0Zii2DlwbEoqEi9PiiQIqv6-64k6cIna4SaRccj0bQ0JuhZ73ub_TpE56kkdgkNsU22O-FiBvsVR8CnC2HZX6vdhGBSbI4Zk8VUHF5


Using weapon swap to cycle between my Burning Arrow setup and Lightning Arrow setup, having Cast on damage taken linked to Temporal Chains, Cold Snap and Immortal Call.

Right now I could use others help to theory craft on the passive tree, the first stop would be EE of course, hopefully with a low level burning arrow and lightning arrow I would be able to advance quickly from the start. Then grab my resists heading down to the Duelist area for Projectile Damage/Leather and Steel.

The reasoning for going after the Projectile Damage nodes over individual ones is mainly due to those nodes affecting both of my attacks, not just one.

This is a very rough draft of the build but it would cycle all 3 elements with only physical damage/defence on non-swap gear.

Any critique is appreciated!