Since everybody seems to love them some companions...I like the idea of having them tiered/structured like WM familiars. The end game being a Rangerish variant instead of giving a bonus to various elemental spell books they would bonus survivals (even if it is a relatively low boost). There could be a spell/beseech that allows you to communicate with others via your companion and utilize the other non-combat versions of familiars. Rough examples:

Wolf: bonus evasion
Falcon: bonus locks
Hawk: bonus athletics
Bobcat: bonus stealths


Gross. That's gross. You're gross.

---
NaOH+HI