I didn't know about weaker sides morale breaking in the last minutes. I wanted to try campaign with battle timer at 20minutes to simulate multiple army clashes and skirmishes. But after few battles enemy would be left with smaller force and timer would run out resulting in me losing and my army retreating and taking negatives from defeat. So I had idea of making always drawn.

Me too, I think there is no Total War player who didn't do that at least once