Would Kovu and Kiara make good rulers?

My biggest problem with SP is the rate in which Kovu changes. The movie could have only shown the span of a few days ( after Kovu is taken in by Simba ). Kovu goes from a murderous outlander to a heroic, righteous pridelander in just a few days. From my point of view, Kovu was trained as a killer before and after he met Kiara at the border. The kind of knowledge just doesn't go away within a few moments. Surely that would rear it's ugly head one way or another. Kovu is no saint and I'm sorry but I think he would make a lousy king. Maybe Simba could teach him how to be a king but here's the thing... Simba wasn't trained either.
He lost Mufasa at a young age and found himself being raised by two care-free friends with no responsibilities. Simba might try and teach him based upon the little knowledge Mufasa managed to show him. I don't think Kiara would know much about being queen either. Nala was never raised as a princess, she was just betrothed to the prince who was then assumed dead after the incident with Mufasa. Kiara is also quite, ditzy and care free as well. She too was raised ( partially ) by Timon and Pumba, who are very care free. Maybe as they would get older they would learn, but I really think they would be terrible leaders.
He lost Mufasa at a young age and found himself being raised by two care-free friends with no responsibilities. Simba might try and teach him based upon the little knowledge Mufasa managed to show him. I don't think Kiara would know much about being queen either. Nala was never raised as a princess, she was just betrothed to the prince who was then assumed dead after the incident with Mufasa. Kiara is also quite, ditzy and care free as well. She too was raised ( partially ) by Timon and Pumba, who are very care free. Maybe as they would get older they would learn, but I really think they would be terrible leaders.