Well I think that anyone should be able to have a familiar no-mater how much magic abilities you have, I sort of see a familiar as your spirit possessing a small animal. In a way I see a familiar as part of you, maybe the spirit of the animal bonds with your soul. Maybe your familiar can have the ability to ?change vessels? in the way of if you find a compatible creature your familiar has the ability to posses that creature instead of the previous animal, this will get your familiar different abilities however, there can be disadvantages to doing this like if you choose a weak animal then your stats of your familiar will weaken. Also you may need to start from scratch on training your familiar as far as skill-wise so if your familiar has really good skills, you don?t want to ?change vessels? or you will loose all the training, & also the previous animal your familiar possessed may attack you with really good skills.
There would definitely be a limited # of vessels to choose from, as the description says that it is usually a small animal like a pet or something. Lets see; cat, small dog, frog, squirrel, bat, raven etc.
(it really depends on what sort of small animals are going to be in Yliakum, these are the type of animals I expect familiars will take shape to, probably going to be more unique small animals then the ones we have on earth but you get the general picture?)