Aura 2h build. Two versions. Please critique/compare.

I've only completed the game in Normal difficulty. I'm hoping some of the people who have done the harder difficulties can help me because I'm not familiar with the challenges faced there.

First, let me elaborate on my intentions with this build. I want to rely on the following Auras for survivability:

Definitely:
Determination,
Grace,
Vitality


Possibly (if necessary):
Purity,
Clarity (if mana becomes a problem)

With these intentions in mind I wanted to take two key passives and made those my priorities. 1. Iron Reflexes, this will convert all the Evasion from Grace into Armor value.
2. Inner Force, this gives a total of 30% increased buff effect (if the smaller ones are added).

The challenge is that these two passives are on completely opposite ends of the Passive Tree. I want to rush to those passives first, ignoring all the side branches. Then I want to slowly get effective passives that are on the trunk so to speak (much later in the endgame).

With that intro here are the passive trees:
Marauder version
Backbone/Trunk:
http://www.pathofexile.com/passive-skill-tree/AAAAAgEAe4whAir2IVXcPcEEeWgLYXgNDq0ppcbYWGNQUIzP9khfP1RJ51LvDrnd1I8ZLiftxPasqnKpfNk8LUz_r2zFivAfBLMUTYM4nYBgbd3zXca1BEVHMtG4kwx9EH_GnlivcLv22jboZKMaVZrMMHXh2qy6l7RVqWCIYVKfyxNbZOdV1ii1705AoCFgdPEY20Oc

Ultimate eventuality:
http://www.pathofexile.com/passive-skill-tree/AAAAAgEAe4whAir2IVXcPcEEeWgLYXgNFHUOrSmlwdjG2FhjUFCMz_ZIXz9USedS7w653dSPGS4n7cT2rKpyqXzZPC1M_69sxYrwHwSzFE2DOJ2AYG3d813GtQRFRzLRuJMMfRB_xp5Yr3C79to26GSjGlWazDB14dqsupe0ValgiGFSn8sTW2TnVdYote9OQKAhYHTxGNtDnKlu74a-u16ffEvsGZ65cbBEDZK7OQ4FLcRYJ9UyCaloogDyL6cwFCBQRxiR974B5-JhlZtlp10AAnF0QVb6iiLA83z1wKZGacQV


Ranger version
Backbone/Trunk:
http://www.pathofexile.com/passive-skill-tree/AAAAAgQAmy34ocKOGbTK0yzp3Q38xVb6dEEUdcHYDq0ppZkrypDd4185LPuE2XgNWK9wu_baNuhhUp_LYIgote9OqW618q6Teri3PsauPC3E9iftrKpyqXzZTP-vbMWK8B8EsxRNZKMaVYM4nYBgbd3zXca1BEVHMtG4kwx9EH_GnkCgBS2plJBsh2phIYTvdO1672BL

Ultimate eventuality:
http://www.pathofexile.com/passive-skill-tree/AAAAAgQAmy34ocKOGbTK0yzp3Q38xWegh3ZKfVb6dEEUdcHYDq0ppZkrypDd4185LPuE2Ud-q8V4DVivcLv22jboYVKfy2CIKLXvTl0AqW618q6Teri3PsauPC3E9iftrKpyqXzZTP-vbMWK8B8EsxRNAnETW2TnVdZkoxpVmswwdeHaMgmpaKIAgzidgGBt3fNdxrUERUcy0biTDH0Qf8ae74a-u16ffEvsGUCgBS2plJ

The two versions are virtually identical in most respects. The only notable difference and basis for comparison is that the Ranger gets no resistance passives, but instead gets higher mana and mana regen and slightly higher HP. The Marauder on the other hand gets 30% resistance to all elements, almost very low mana regen increase, and less notably 50% more armor.

Mana Values:
Ranger: Pool 36%/ Regen 40%/ Cost Reduction 52%

Marauder: Pool 24%/ Regen 20%/ Cost Reduction 57%
---------

I'm not sure if the resistance bonus of the Maurauder is enough to outweigh the lower mana regen. Also not sure if mana upkeep will become a problem at endgame (remember I'm going to be using Auras (with 20% lower reservation costs but still)).

Read this thread, it will help you.

I see no tank over here. More like str nodes collection. And mana reduction.

Maybe tanky was not the right word. Maybe Aura dependent build. Again the main reason I went to the two opposite sides of the tree is to gain (hopefully) very high defense from Determination and Grace, both improved with the Inner Force passive.

Changed thread title.

The problem with your idea is that Inner Force increases a BUFF (AURAS), whilst armour nodes and evasion nodes and armor-evasion nodes increase ALL OF IT (THE AURAS AND THE ARMOUR FROM EQUIPMENT).
It's no worth it to reach Inner Force, if you can get other passives which are closed and are much more effective (Armour Skin - Leather and Armour - Reflexes).
In conclusion, don't get Inner Force.

I understand what you are saying, but the reason an increase in the buff is attractive to me is because the buff bonus (from Determination in particular) is multiplicative as opposed to additive. I'm not sure about the order of calculations when it comes to Grace.

To be honest it's a bit over my head due to lack of information, but what I do know is multiplicative percentage calculations generally yield higher results than additive...?

I could be wrong.

Oh yeah, and I realized I forgot to mention the Vitality Aura. Editted original post.

If you take Inner Force the the other 2 regular nodes you will get an additional buff effect of 30%.
Level 1 Determination will increased by a 10%. if you have 1500 Armour from items and your armour passives add a 100% (1500) it will turn into 3000*1,1=3300, so 300 additional armour.
If you do not take Inner Force, and all those nodes and take just 1 Armour Skin node, you add 500. If you add 2 normal nodes of armour (10%), you add 300. Although, Inner Force will buff up Grace and Vitality, but they are not multiplicative, they are additive.

Even if you add Grace+Inner Force+IR+Determination, i have the feeling that it won't be worth it. One of the most important tips is that to have better survival in this game, is not to focus only in 1 stat.