Exactly, obviously one can invent house rule as one wished, but beast change involves an actual change into an actual animal. That's more than a flavour thing, since changing into an actual beast has significant drawbacks like robing you of your ability to speak, possibly to cast magic and it tends to attract unfavorable attention at mundane cocktail parties. Beast change without the actual beast change is a far more powerful ability that effectively increases the number of skill points available to the character by a huge margin. At -1 refresh it's ludicrously overpowered compared to other powers and stunts that in some way gives you access to additional skill points and there'd be virtually no reason for any character not to take it.
My point was mainly about trying to use it purely for for the skill-change without any actual shape-change. Personally I think using it for something with functional hands and/or speech is questionable, but a minotaur isn't that unreasonable, a pure skill-swap with no shape-change or changing into another human IMO is.
Were-Parrot/Crow/Raven (speech).
Were-Monkey/Chimp/Gorrilla (sign language/writing/opposable thumbs).
I can't imagine why a wizard would not be able to cast magic after shapeshifting, given that shapeshifting is itself magic. Furthermore, unlike, say, Living Dead, there are no social penalties for Beast Change(the changes are "only ... cosmetic").
Finally, True Shapeshifting gives you the ability to use infinitely many skillsets without requiring the beast part of it. The fact that you can rearrange your skills however you want, whenever you want, is more than enough to justify the increase from -1 to -4.
