Spiders, Panthers, and other druid wildshape forms should allow the druid in question to be able to scale cliffs and other physical hindrances with ease.
So I suggest giving these forms the scripted power to do so.
Yes, yes indeed please.
Maybe not with ease, but a +XX to climbing may fit.
I think it's more that it's not possible to use non-potion items while shapeshifted/polymorphed. As Climbing Claws are a Miscellaneous item, a Druid can't use them in spider shape, even though spiders are pretty darn good at scaling surfaces.
Therefore, if PCs with Polymorph or Wildshape got to use the Climb power as a Player Tool that only worked in spider/cat/certain other forms, they would be able to use it without changing back. It's not just Druids that get to turn into spiders; Wizards, Sorcerers and Animal Domain Clerics can too.