Criticism on my Allrounder Build

http://www.pathofexile.com/passive-skill-tree/AAAAAgEBxthYYz38fLgpLmebrj534zwtxPbEFcautz56uGz2rpNuqjJ-tfKpbngNWK9GaTboOlLfv4ZgVgRhUmCIKLXvTkCgIWB08RjbQ5wOrSmlW6_dDTqzkAqfywUtYEt673TtnrlQUIzP9khfP9SPud3vDvIvhyk9DySLfLvFivAfogAEswJxFE2paDrY7DgaOKeEkFW-igHcG_qkGSXfhNlHfmVNFFKrxb6nTeOsWf6Pplc64Yjx_gryRedjVamXtKy64don7ayqcql82fzFZ6CHdkp93sbqYkGHgseVIFv0

So heres my build. It has the idea to be a little allrounder although i dont know if it works. Through Iron Grip + Blood Magic + the high Health/strength(530) u can use any projectile attack doesnt matter if spell, bow or wand and u can be a melee player aswell cause iron reflexes gives u good armor and and resolute technique eliminates the need of accuracy.

This is just theoricrafting atm cause im just lvl 19 and dont even have blood magic. Im also not sure about condult cause i dont think i can use many auras? Or only with lesser mana gem. And i dont know if arcane effiency(10% reduced mana cost of skills) is worth it. As i think it would also take less hp right?

So tell me your thought about this build.

I have one more question. Do auras take percentage of mana or a fixed part?