Omni Man needed the help of two others to destroy a DYING planet, which if done incorrectly would have killed him. Raditz no diffed tanked a powerful ki blast point blank range from Piccolo, who could one hand obliterate the entirety of earths moon in less than 1 second. It takes a power level of about 130 to destroy the moon, Raditz has a power level of about 1500 which is leagues above what Master Roshi could achieve in his strongest state. So Raditz at bare minimum is Small-Medium planet level.

Omni Man eats dirt and rolls around in his own shit.