Level 1:
Savagery I (Ex): As an Immediate action, you may spend 1 Beast Point and make a DC 15 Combative check to add +1d4 damage to your next successful attack with your natural weapons. You gain an additional +1d4 for each 5 points you exceed the DC.
Alright.

Level 11:
Savagery II (Ex): (requires Savagery I) As an Immediate action, you may spend 3 Beast Points and make a DC 24 Combative check to add +1d8 damage to your next successful attack with your natural weapons. You gain an additional +1d8 for each 5 points you exceed the DC.
Already, I see a problem. You're spending 3 times the amount you spent on the first version for (on average) two extra damage. That's 2 BP for 2 damage. Not only that, but the DC is increased by a lot.

Let's say you qualify for both of these. You take both. Alright. Spend 1 BP on the first one for (level 11 beast warrior has 14 ranks and 14 Wis) +16 to your check. Automatic success, plus the likelihood of exceeding it by 10 for an extra 2d4 damage. Total -- 3d4 damage.

Same situation (level 11 beast warrior, 14 ranks, 14 Wis) spends 3 BP on the second version. With +16, you can assume you'll get the DC, but probably won't exceed it by 5 or more consistently for a while. +1d8 vs. +3d4. Not even close.

I recommend raising the damage bonus to 2d8 (9 average) or 2d10 (11 average) for the second version. That way, 3d4 (7.5 average) doesn't really compete. It shouldn't, considering you're spending only 1 BP on it.

I'd like to see some special effects added in too. Maybe make the damage 2d6 or 2d8, and add in some sort of status effect.

Level 20:
Supreme Savagery (Ex): (requires Savagery II) As an Immediate action, you may spend 5 Beast Points and make a DC 30 Combative check to add +1d12 damage to your next successful attack with your natural weapons. You gain an additional +1d12 for each 5 points you exceed the DC.
Same goes for here as above, except the DC is slightly more reasonable.