Updated. Are we done here?
There's something funny in the Hit Dice:
Hit Dice: 1d10+4 (9 hp)
Where did that +4 come from? They only have Con 10 and don't have Toughness.
Surely it should be 1d10 (5 hp)?
As a 1 Hit Dice Magical Beast it should have a +1 BAB, and hence a Grapple of -12.
Its bite should also be +5 melee: +1 BAB +2 size +2 Dex (Finesse)
Also, its Spot ought to be +12, not +16.
4 skill ranks plus 2 Wisdom bonus plus 6 racial = 4 + 2 + 6 = 6 + 6 = 12!
We discussed putting some points in Tumble. Maybe put 2 points apiece in Spot and Tumble for Spot +10, Tumble +4? We could even put all 4 ranks in Tumble, which would drop Spot to +8 and give them +6 Tumble.
However, they're "clumsy fliers" so I currently prefer just sticking to their current skills plus Flyby Attack and Mobility.
That would make the following changes:
Hit Dice: 1d10+4 (9 hp)
Base Attack/Grapple: +1/–12
Attack: Bite +5 melee (1d3–5)
Full Attack: Bite +5 melee (1d3–5)
Skills: Spot +12