Barbarian dip normally only gives 1 rage per day, anyway, so you're getting more rage regardless.
Also, your rage pool is not that small at all. With 2 levels of Barbarian it will be 6+Con rounds, which should last 3-4 encounters. With 4 levels it will be 8+Con rounds, which should last 4-5. Oh, and don't get Moment of Clarity. Quite possibly the worst Rage Power ever.