What do you mean by "spike-y"? That's not how I think of higher dimensional spheres at all.
Dimension 3, put 8 spheres radius 1 at (1, 1, 1), ... Then from the outside you can touch the inner sphere (and it's a bit bigger).
Once you get to a certain dimension (10 IIRC), the inner sphere is no longer in the convex hull of the outer spheres, it is "poking out" of the arrangement.
Spiky like that.
By the way, this is a similar phenomena to the 'curse of dimensionality' [1]