@AmiDelf:
My thinking is that it wouldnt be much of a difference between this computer and an AmigaOne/Pegasos equipped with a AGP-card containing a Virtua3D chipset.
The graphics core of the Virtua3D chipset found in the Dreamcast is actually a Power VR Series II graphics processor. To give a little hint - the Power VR Series III was used in the Kyro1 and Kyro2 graphic cards.
So if you stuck a Kyro1 or a Kyro2 graphic card in an AmigaOne/Pegasos you have quite the same machine as the one you intended... a bit better performing minus the Zorro slots and Amiga/Atari/C64/etc joyports.
/Patrik