I love the MC's progression so far. He started out with the mindset of staying on the sidelines while giving out future knowledge while staying away from any limelight. That slowly changes to him diving deep into the struggles and heroics into creating the abilities he came to know as common place in the future. He see's selfless sacrifice, he shows genuine maturity which coincides with a regressor. He has gotten in plenty of situations where he could face slap a young master and make an enemy, only to instead, turn that person into a friend and companion. Great story.