Hey, Merry Xmas to you too.>>3280906
As far as reasonable ones? Probably that he's way older than he really is. He's wise for his years but he's still ridiculously young, barely mid 20s. That might seem old to literal children, and the hair doesn't help, but by normal standards he's an overachieving baby. Too young to have gone through as much as he did. Another is that he literally raised his best friend since early childhood like he was his adoptive father when they only knew each other for a couple of (impressionable) years beforehand.
His greatest fear after not being to achieve everything he wanted before dying young is that his trauma left him too broken to function and protect those he cares for. He does his best, he's still generally a sweet guy overall, but these two traits together can drive him to overcompensate. He's a terrible backseat driver, and it takes literally ripping him from his seat of authority to force him to eventually back down. He's still restless afterward, but he eventually learns to accept that he doesn't always have to be on the front lines to be useful and is fine captaining from the back row.
Unfortunately the last season introduced a ton of questions it never bothered to answer AND the EPs refuse to ever talk to the fandom again. But chief among them is the dreaded literal last-second love interest. Don't get me wrong, the guy is cute and all, and it's great he got a good ending, I don't want to sound ungrateful or anything, but the circumstances make it an obvious case of sloppy corporate-mandated PR bandaid that doesn't jive well with his established personality so it just creates bigger problems. Another outstanding question is how retrieving his transforming weapon was a huge plot point in the early seasons. It made sense to have no answer because he "died", but he came back so that they still never let him use it now looks silly. Especially since it's said the form it takes gives insight on the user.