As for replay, I have two options:
1. On any down, review change of possession and score/no score. That's it.
2. On 1st and 2nd down, no reviews (other than the two above).
3. On 3rd down review it all.
4. On 4th down that is not a punt, review it all.
Only reviewable play involves change of possession or potential change of possession.
I think we can all agree that the refs are human. Well, at least most of them. Which means:
They will make mistakes.
They may not be unbiased in regard to teams and/or players.
They may have vices that interfere with their judgement.
They may have physical deficiencies that affect their ability to make a call correctly.
They have a life outside of football that may affect them while on the job.
Unfortunately, the best sport has the worst officials. First thing I do now after every play is look at the bottom right of the screen to see if the box turns yellow. It's awful.