I think replaying the same map 5 times is tedious... =)
although 5 times a month might be okay, or 4 times, once a week...
but I still think it would be more interesting to play it once (not everyone has time to sit and replay it all day) and have everyone on equal footing, whoever navigates the map better, whoever gets lucky, wins...

You are confusing an online tournament with an offline tournament. What does it mean to play on equal footing once for an offline tournament? How will you check if a player has played the map once or a hundred times? So, by urging everyone to play the map only once, are you planning to replay it three times yourself, thereby proposing to remove the equal conditions for everyone, which for an offline tournament means: whoever wants to and can replay it as many times as they want. Furthermore, I agree that quantity can turn into quality, but not always. However, that's why there is such a thing as map reconnaissance in an offline tournament. In other words, it's a quick playthrough of the map using the map editor, cheat codes, and whatever you want. Based on this, you plan a clean playthrough of the map (here you can only use what the rules of the tournament allow). The better you do the reconnaissance, the fewer times you need to do a clean playthrough to improve the result. Ideally, after reconnaissance and a clean playthrough, you may not need to play the map again. Luck is, of course, also an important factor, but in an offline tournament, its influence is less than in an online tournament. This is what distinguishes these types of tournaments ;)

Added after 4 minutes

Playing from the same save, the rating depends ONLY on the number of days.
POINTS = [ R*(200 - [N*K]) ],
where N is the number of days spent,
R is the rating (you can see it as a percentage on the "Scenario Information" screen in the game.),
K is the map size coefficient, equal to 1.4 for Small, 1 for Medium, 0.8 for Large, 0.6 for X-Large.
After the value of N*K reaches 60, each subsequent day counts as half a day, after
120 - as a quarter of a day, and, reaching 180, it stops growing altogether.
If victory is achieved during the computer's turn between days N and N+1,
the result will use N+1.
The rating R depends on the starting conditions and the difficulty of the map. For
Easy/Easy, it is 50%, increasing the map difficulty gives {+20%, +40%, +80%},
and increasing the initial conditions - {+30%, +50%, +70%, +90%}.

I calculated my playthrough of the second stage using this formula. To get the result not as a percentage, you also need to divide the resulting number by 100. The result matched. However, it rounds incorrectly ;)