Thanks for your fairly complete list of supported Powermac G4 versions. There are some points which I want to annotate.
"PowerMac3,3: --4 x DIMM banks; --Supports PC100 SDRAM (Max 1.5GB); ----3.3V, 168-pin, unbuffered, non-registered (does not mention non-ECC or non-parity); ----Maximum of 16 devices (ie may be double-sided, but no more than 16 chips in total) per DIMM. [4]"
I think you mean the maximum memory which this model can use, not only the maximum MorphOS can use. Mac OS X can use the full 2 GB of RAM in the PowerMac3,3.
And some of the older PowerMac 3,1 - 3,5 support only harddrives < 128 GByte on the internal ATA controllers, don't know if it will affect MorphOS.