My thought (& based on the 2 families I know with 6+ children) is rather than focus on the routine of one child, look at the big picture of what everyone needs.
He's still little (esp with adjusted age) & so really still young to be worrying too much about a set routine of sleep. I'd be inclined to do what works best, if he wakes at 30mins & he will sleep longer if in a sling/carrier then put him in a sling & get on with what you need to with the rest of the family.
In terms of at night, unfortunately it's normal to have unsettled periods & like with my DS2 very annoying when it's at 1am rather than 5pm.
I think we live in a world that we want things "right" when we are tired & struggling with a new baby, we do have the hope "if I get the sleep right, I will be less tired" where as (this is from a BTDT) there will always be another thing that is a challenge, so trying to learn to look at what is good rather than focus on the struggles is actually a path that is easier.