Vulpinals are also small so they fit inside an Emergency Force Sphere while being summoned and then healing your poor cowardly wizard who was just beaten by a nasty critter.
Speaking from experience, here.
OK....
Sacred Summons gives you a standard action instead of a full orund.
Vulpinal does not HEAL it removes disease 3 times a day and lays on hands 6 time a day.
Its a 5th level spell.
It is probably a little less useful in combat then a Bralani (also summonable with the same spell) but a little more useful out of combat. Seems reasonably balanced to me.
How is a bralani even close?
It got 2 ligbting bolts and a bow.
Healing be can heal 3d8+6×2 or avg of 36.The agathion on the other hand :
3 holy smite (way better area thab lighting)
3 charm monster (ultimate controll the brute spell)
3,dispel evil that allow auto dispel magic and effects
Heal 6×3d6 or avg of 60.
Also, with 3 knowledge of 21, he is a summoned sage!
Flight, it can cast wind walk on itself (which is just a better gaseous form, so it still has DR 10/ magic, which may or may not be useful), and it can use both its SLAs and a fairly basic but at will cone ability while in that wind form.
Not saying it is more versatile, but it has its uses.