I also don't use auto taxations/building and do everything myself.
However, I just give orders as I see them. Scroll around the (hugely laggy) campaign map and scout for settlements missing the construction icon and let them do something.
Before ending my turn, I do a quick check on the cities tab whether I missed any settlement or not.
That way you also don't lose turns waiting for other settlements to finish their building and you won't have every place identical.