Just let people play their characters how THEY want to.
I agree with this.
Only problem I see is that alot of people treat their animal companions like pets, and don't take any time to RP with them. You can call your bear fluffy but he's not a little animal puppet!
You aren't a hunter from World of Warcraft guys, your companions should mean something to you, they're not just pets for tanking to be replaced without a care when they die.