I guess it'd be really fun to interact with helpful creatures although this shouldn't get out of hand! I mean: it's true they should've various levels of intelligence but if they get TOO intelligent or smarty-pants, then the various animal groups and hierachies might become rather inbalanced. Imagine a group of unicorns trying to challenge the authorities of of their own species which in turn causes conflicts with other species(sentient or non-sentient).
Also, although this sounds fun: I wonder if it adds complexity to various issues 'cos having friendly creatures can also put them in conflict with others(animals, beings, humans, etc.). Unless it truly has a great effect on the gameworld, I'm all for them being almost non-sentient.
Although it'd be really neat to have a pet whom you could even turn into a familiar or aid.
