I suggested something similar in katane. Have morale based on number of city takes. It increases 25% for each city till you’re at 100. Morale basically goes away after thatI've recommended this before and here goes again. IF you're going to have morale, it should go away after a player's been in a world for more than a few weeks..
Morale for a new player? OK
Morale for someone who's been in that world for more than 60 days? No bueno.
The above suggestions can be worked around by having the LMD restart or just replacing LMDs. It could slow things down but won't get rid of the issue like this update does.