Par is a guide, not always accurate, but a reference. Based upon a basic configuration of length, it is merely a guide. for me it is best when the yardages overlap and the par also blurs. A suggested score for a reasonably skilled golfer per hole. I don't like the concept of "Total Par" for a course as it blurs back and forth.
Par 3 - up to 280 yards, depending on all factors
Par 4 - from 250 yards to maybe 520 yards, based upon all factors
Par 5 - from 460 to (6-something) based upon all factors
I would like to see holes listed on a card as a par 3-4 or a par 4-5 as well as the rigid 3, 4, and 5.
Total par-a guide, not always a Michelin or AAA guide, but a reference. Don't care for it much. Maybe if it too were par 70-72.
Although...... scores for the day are best referenced by total score (68 or 81, if you must) rather than 3-under or 4-over. But best - Joe beat Frank 3 up.