Some good advice there, but I would add a few points.
Yes, you care mainly about remaining duration, but to get to that you will have to ask some other questions first.
Make sure that you have set the status date in project information.
In any case where a task has an actual anything, such as actual start date, actual duration, actual finish, these must have occurred in the past relative to the status date.
In any case where someting is scheduled, ie scheduled start date, scheduled duration, scheduled finish date, then these must all always be in the future relative to the status date.
This is the date up to which progress is being reported, the date you conduct your inspection or the date that the subbies report (only one date, not separate dates for each subbie).
Mainly start with the facts, and proceed from there to the estimates, in this case the remaining duration.
If the task has started then there must be an actual start date.
If the task has finished then there must be an actual finish date.
If the task has started, and has an actual start date.
You care about the remaining duration for any task which is in progress.
You also care about tasks where the remaining duration = total duration (and therefore actual duration = 0).
You also care about tasks where remaining duration = 0, because these tasks maust have actually started and actually finished. If they did, then you need to know when they actually started and actually finished. This comes from accurate and reliable records kept on site.
Do not insert those various columns/fields into the Entry Table.
Use the Tracking Table instead.
Do not type % Complete.