Newbie needs help about the weapon to use

Hi,

I'm a lvl 29 marauder and I started building him for the infernal blow 2-handed build.

Since the build is pretty similar to ground slam build (and I still don't really know how any of them will play in late game), I'm currently unsure how to allocate the points and if I should focus on a 1-handed + shield or 2 handed build.

So, my idea right now would be to spec for all the common things (life, resist, armor) and I'm not spending points for offence.

Is it safe to choose to take +% maces damage as passives, so that I can either use 1h or 2h (or maybe both switching between gear), or is it almost impossible to find a good weapon of a specific kind? Moreover, I read that IB explosion doesn't scale off weapon damage, and I should look for +% damage for 1/2h, but at that point I should commit to that.

What would you suggest?
Where should I put those points?