Baldur's Gate : The Sword Coast Chronicles : NWN2 Persistent World

I've a hard time making a working build.

At the moment I'm at 11 barb 6 fighter/10BW/3 First of the forest.

I've also been thinking about 10 WOD/10bear/3fist/7 barb. (wod for feats/elemental weapon damage)
Both builds go with 22 con at the end for 3x epic damage reduction and 2x fast healing.

The biggest problem the builds have is only 4-5 times rage, though increasing barb levels seem to be pointless sine bear warrior doesn't benefit from them.

Any suggestions?

Barb lvls do add rages and DR, so they are not always pointless. Still, more importantly, there is the Extra Rage feat (available on items as well). That, together with the Extend Rage feat line (the first two are free from the BW class) should eventually make your rages last all the way through the rest timer. Until then, your BW should be at least decent even outside Bear Shape.

I'd recommend B 10/Fighter 6/WOD 4/BW 10, since B gets a DR point and extra feat at 10 (the feat can be in the Epics) and another rage at 8. You can go either for DR or incredible Knockdown power with this. Both variants are very powerful.