@countzero
Zorro 2 is the bottleneck here, not the Cirrus2. It does quite well in 16 bits 800x600. Picasso II is just the right choice for a Z2 system. PIV is overkill.
I notice a lot the slowness when switching the PicassoII from 256colours to 16bits.... it's specially noticeable on intuition menus (and I mean standard ones, not using MagicMenu patches).
That problem happens regardless of using ZorroII or ZorroIII as that Cirrus chip is slow (compared to other gfx cards). Just try out a GVP Spectrum with the same chip in ZorroIII mode and you'll see that it's not instantaneous like a card with a faster blitter like CV64, CV64/3D, PicassoIV...
I agree that it's better than nothing but I would seek a CV3D as it allows higher resolutions and it's way faster.