I think each character should be able to have their own personal companion.
The pet does not really do much but act as an Ant slave.
You would be able to name it(Nothing derogatory or unallowed)
You could have a whistle or some item to basically "summon" it.
The item would not disappear.
The item will also not disappear if the owner dies.(Would be very unfair in my opinion)
There would be commands similar to the Ant slave, such as wait and follow.
Players would be able to change the animal from the EL shop.
The animals should mainly be like the wild animals in the game, but nothing to big.(Such as bears)
I do know that this require a great deal of work, but I think the developers should be able to create this using the basis of the summoning programming.
I also know that there are many ways this may not work, but I do see it as a possibility.