Yes, that would help.
In general:
Requirements: BAB +6, rage class feature...
BAB 3/4, good saves fort.
1 Wild Empathy (as the druid class feature).
2 Rage +1/day
3 Lesser raging shape
4 Natural Armor +1 (permanently in effect)
5 Rage +2/day
6 Raging shape
7 Greater Rage (as barbarian)
8 Natural Armor +2
9 Hybrid shape
10 Rage +3/day, controlled shape.
Lesser Raging Shape: When raging, if he so chooses, the barbarian grows claws and a bite, a d6 each, +3 natural armor, faster movement, he's not quite animal shaped, but kind of bestial. Give him a claw/claw/bite natural attack routine.
Raging Shape: Can be an animal, as wild shape, of his size or smaller, for the duration of rage.
Hybrid shape: A war form, like from werewolf:the apocalypse, I suppose. Larger than his normal form by one category, you've got the bonuses from greater rage already, mechanically I would work with the player to advance a couple of animals to large size and just describe them as hybrid werewolf/bear/panther whatever looking forms. He could use claws or weapons, whatever he liked.
Controlled shaping: The barbarian can burn 1 rage use to wild shape, without having to be enraged; useful for non-combat stuff. Duration is hours=his new Con bonus.