Lightning arrow Marauder passive tree help.

Hey guys, I just finished the normal difficulty of the game and it was awesome!

Before I go any further, could you guys guide me on where to go from here on the skill tree to have an effective lightning arrow build for a marauder?:)
http://www.pathofexile.com/passive-skill-tree/AAAAAgEABLMWbxkuGjgdFCftMok9D1BQVElVxlfiWGNZ818_Zp5nvXflffWMz49GkFWboaIAp4SsqrndwBrEFcT2xtjPZdDQ1I_nUuw47w7wH_Iv9kj60g==

Thanks!

^