It's just about strictly better than a barbarian, balance-wise. It can wear armor, has fighter-like weapon skills, and has even better skills. Up until level 10, at least, where it doesn't get the rage improvements, but even then, it has more attack/damage thanks to the fighter transplants.

It's just...better. More DR, more attack/damage, can wear armor, etc. The one "powerful" ability I see is Reckless Advantage, which in addition to not precisely explaining how it works, gives the class a massive advantage when combined with crit-builds (say, a scythe with some critical feats).

Some abilities are nonsensical- note that Strength of the Forsaken literally doesn't work with multiclassing.

You say this is v4? What changes have you made?