functional pets are pretty good as long as everyone can get them. like in rappelz, everyone had the same chances of caching pets, that was awesome. rappelz had the best pet system out there, i miss it
training/grinding up your pet can be very motivating
The pet system in rappelz prolly was the one i liked the most among all mmorpgs...however the way to obtain them was quite bad...(not taming, but grinding for cards)