So, Ill be forthright and to the point.
I had mind to make a feedback thread of this, but have spoken of the matter with many, players and devs alike.
As is, barb feels... weird. At low levels it does nice but its scaling is awkward, the immense feat tax (especially for EDR if you go that route) hurts, and worst of all? The flow feels all wrong. Going from your rage benefits to nothing hurts and feels awkward with the enforced one minute CD, and the fact that rage only comes with mighty hurts.
With that said, I would like to suggest that, unless barb is slated for some minor rework, rage should be made a toggle a la defensive stance, perhaps with some malus like a reduction to concentration or some such. Numbers too can be decreased for the QoL of just rage being a toggle.
Similarly, a bit of scaling regen may be nice, such as one per 7 levels. This would pair nicely with mighty, but more importantly give some big QoL at low levels and a bit of love for EDR barb whose feattax is costly.