This is a global game, limiting to set times is going to make people less likely to play not more.

I could get maybe giving alliance a timer before an emperor is dethroned or crowned after taking emperorship keeps, but otherwise no.

Though I would like to see things slowed down a little, maybe through allowing guilds who own a keep or resource the ability to use wood, stone, and siege engine kits to build improvements to keeps and resources that make them harder to take, like a med tent that allows a limited number of respawns per hour, a siege engineer work shop that increases deployable number and stops defender siege weapons from taking the base degrade damage, or an armory that increases guild member's power when in the locals range.

Also adding bonus locations to fight over like making towns capturable and some places capturable as well.