Too much tank?

139% extra health, some armor, and life regen, and life steal..

just wondering is it not enough damage?

doing the math, i just have 932 health (excluding gear)

1. Learn to link builds.
2. I would call it more offensive, than defensive. You get damage from weapons, not skill-tree with melee marauder.

Forget about this life gain on hit crap there, every life leech you need comes from support gems, no need to waste points on it, get some resistances instead because you've got an extreme lack of defensive there.

Then head for Iron Reflexes and grab Unwavering Stance after that, should be fine with the survivability then even though you've invested quite a bit in damage nodes.