this is late and i'm late but what the heck. the above responses are pretty on spot for the majority of shiro, but something else not mentioned here is he's as much of a goofy human as the rest of them.

back when season 1 aired, josh said he voiced shiro "as their peer", not as a leader, or a mentor, or a dad/adult. when they're joking around about the laser sounds, yeah shiro tries to redirect them, but he also stops for a second to make his own laser noises. he joined in that asteroid-snowball fight, the food fight.

basically, he knows when to be serious and coral the paladins into what they need to be doing. he definitely has near-infinite patience and he's seen some shit. but he's not that much older than them and he has fun with them too. seeing people talk and play shiro as the Dad And Only The Dad Ever put me off playing outside of psls, so I wish you the best luck anon!