Point threshold?

[Sanctaphrax]

I thought Lycanthropes got some minor physical changes during their time of the month. And even if they don't, the Power writeup is clear. Human Form is about shapeshifting.

[Theogony_IX]

No, lycanthopes only go through mental and spiritual changes, not physical changes.  They gain powers, but their outsides stay the same.

YS79: 

Let’s get this clear up front: lycanthropes are not werewolves—though they share some traits in common. But where werewolves change their bodies, lycanthropes change only their minds, aligning their thoughts and senses with those of a beast.

It seems "shapeshifting" can apply to internal shifts and not just external shifts.

EDIT:  Beast Change is the power that dictates external shifts.

[Sanctaphrax]

Human Form says

Specify which of your supernatural abilities (usually most or all of them) are unavailable to you when you're not shapeshifted into your "powered" form.

I guess you can stretch that description to fit a lycanthrope-style mental change. But it doesn't really work for someone who's stronger while touching the ground.

[blackstaff67]

Yeah, I'm not sure I like the shape that Power has taken "in the wild". It's more of a Power-writing guideline than an actual Power, and many people use it pretty unwisely.

Still, I think it's less abusable than the canonical rebates. Like Cadd says, it scales. That alone shuts down a lot of degenerate stuff.

Not really. Human Form denotes a change of, well, form. Earth elementals stay the same shape when they leave the ground. And Involuntary Human Form without changing form is just Limitation with a non-scaling cost.

What about a human that changes into an 'ultimate warrior form' with armor and powers? 

[Sanctaphrax]

Sure, Human Form can do that.

I'd still rather use Limitation, though. I prefer the cost to scale with the size of the drawback, and I don't mind doing some extra math.