I'd actually say Majora is more dangerous and powerful than Ganondorf, much like how Discord is more dangerous and powerful than Nightmare Moon. While Ganondorf has a logic to his evil, Majora is pure chaotic insanity. Also, in my head-canon, Majora is basically the Terminian counterpart of Demise. So yeah, Child Link took on a being of Demise's strength and won. That's awesome.