Ryu’s life is ALL Martial Arts, 100% dedication, its all he does.
Ken’s life is normal (wife and kid on the way) and martial arts is more like a serious hobby. So he doesn’t commit due to having a life.
But they are on the same skill level in canon, which MEANS that Ken has more potential and is therefor the stronger character.
Ken = Casual Player
Ryu = Competitive Player
Ken > Ryu
Try to disprove this, I dare you. Also move to fanfic section if it needs to be there.