For systems I finally acquired, Castlevania: Dawn of Sorrow (DS) and Gradius III/IV (PS2).
I own the following but have yet to own a system:
Downland and Slay the Nereis for the Tandy CoCo
A few VIC-20 games
Ys III for the PC-9801
Parodius and Quarth for the X68000
I, Cyborg for the Vectrex