Not to state the obvious, but are you running the Enforcer? It is required for ZII and C64/3D, and at least on my A2000/030 it was like night and day. Without it, everythinh was soooo slow, including redrawing of windows, icons, etc. With Enforcer running, everything zips along. In fact, at 1024x768 it doesn't seem significantly slower than on an A4000...
Polbit
