2Senator

Right now, we are discussing changes to the rules, aren't we? But what's the point of creating rules that will initially contain loopholes for military tricks/cheating?

I repeat, most of the rules, and all those concerning combat, contain loopholes. A restriction on morale will certainly be "flawed," but not more "flawed" than everything else.

1. Should the organizer indicate which battles, in his opinion, are key before the start of the tournament?

It's generally not advisable to indicate this. But it's worth deciding for yourself.
An experienced player can, with a high degree of probability, suspect obvious cheating even in the final, and detecting it with save files from the end of the game will be close to 100%.

2. Does this mean that all intermediate battles should be played without losses by default?

Even perfect morale and luck will not guarantee a smooth playthrough without losses when playing for speed.

What is a "routine" battle anyway? Is a single conservative unit a "routine" battle? It depends on what army I'm going to use!!! The same applies to dividing battles into long/short ones. And this approach applies to each battle.

If the organizer has at least 1 save from the day (and often not even that is needed), the organizer can easily distinguish a routine battle from a difficult one.

Changes to the rules should eliminate the use of cheats in all "competing groups."

Unfortunately, this is absolutely impossible.
But there is, in my opinion, an effective proposal.
Currently, the top players are checked, and the organizer makes the selection. It could be made mandatory to check a certain percentage of participants in addition to the winners. The participants to be checked are chosen randomly.
It will be scary to cheat because you become a cheater once (just like a traitor). It will be VERY difficult to restore your reputation.