So far characters have been surviving more. Compared, his kill power is not weaker. He also gets more benefits from rage than others.
You're wrong. Compared to Brawl, and compared to the new methods and actuality of survivability in this game, Ganon will have a tougher time killing.
Most of his KO moves in Brawl were nerfed in power this game. His Dash attack, DAir and UAir are examples. They were brilliant kill moves if you used them properly because of their speed and/or sheerknock back alone.
With that said, Ganon will have an easier time landing hits this game. He may also kill better, faster and more efficiently than in Brawl. Some of his moves which could ha e KOed in Brawl but the moves itself were not as good have actually improved. His aerial Wizkick is an example. BAir, too - this move has improved drastically in speed and power from what I can tell. And I'm quite sure that BAir, as the metagame advances, will be one of Ganon's most use KOing move.
The rage effect will benefit Ganon, just as it will benefit all other characters. But during some cases, it will indeed benefit heavy hitters more.
Basically, Ganon has lower kill power in this game keeping in mind the attributes and mechanics of THIS game, as he did compared to brawl. But, Ganon will land hits with more ease, and have an easier time avoiding projectiles and other moves. So there is a trade off, and we can tell that this trade would definitely
help Ganon more, but we won't be able to tell if this trade off would be more beneficial overall and as the metagame advances. It may, or it may not.