It's an interesting list, though. I would go for it if I handn't the familar list in the game, but I have it and probably Brian's list is a better starting point for me.
In the end, I'll allow multiple bonded animals, but with restriction based on the level.
The elephant situation is a false problem, I think. If you are in such situation, start putting your party in places where the elephant is not an advantage but a burden: city adventures, mine, underground mission, infiltration...
He'll start to think that something more discrete cuold be a better option.