1d8 for claw damage is ok IMO.
For natural armor I think something in the range of 10-15; his focus is on the offense. In any case, he could wear armor, maybe a +5 studded leather with some special abilities for a total AC of +41-46; different types of AC are always good from a design perspective, right?.
For poison I'd say Dex damage: Con damage would probably merit an increase in the CR of this scion.
BTW, I think there are still some issues with the skills. Reading the updated conversion notes, I noticed tumble synergyses with balance, so balance should be 57 (38+15+4).