I think the biggest problem with Katsuya is that he accidentally surrounded himself with idiots and yes men who can't think for themselves and rely in him for every little thing. Then when they finally try to be independent and like Katsuya they don't have the skills to back it up.
Ironically...
To be fair realizing that he is not meant to be a leader but a soldier is probably the smartest decision he made. Just because someone is a great fighter doesn't mean they're a great leader. Him passing it off to Yumina who is able and willing to get her hands dirty and make the tough decisions...