Actually, not like that at all. In PnP, improved unarmed strike is feat pretty much anyone can take, all it does is allow you to do lethal damage with unarmed strikes (and maybe ups the damage to 1d6). In DDO, I imagine that would just make you not attack at sloth speed. Monks get it as a bonus feat. Rage, frenzy, etc are not feats in PnP you have to take appropriate classes to use them.
And for all intents and purposes, you can't make an unarmed barb in DDO, because without the feat, its beyond silly, with it, it would at least be kind of reasonable.
Its not an earth finisher, or finisher at all, its a strike you take with enhancements.