Many "dome" pistons really kill any charge motion in the cylinder as the piston approaches TDC. As it was mentioned, the piston crown has to be treated like the floor of the chamber.

This engine is not DI, and DI piston crown features are only present for catalyst light off, to keep a rich pocket of fuel at the spark plug. Pistons in central mounted DI injector engines will look similar, albeit less exaggerated, as they want to maintain some quench along the outside of the chamber, and you have to build up material in the center to gain back CR, but not so much as to "cut" the chamber in half at TDC.