The leaders of the country sure didn't give it alot of thought about choosing a successor. Or ad groundrules that when Tsunade wakens from her coma that she'd be reinstated again instead of making Danzou the 6th. They should have just made him temporary regent.

I still think they should have plans ready who would succeed her before something happened to her, every country this day has a vice-president or something similar who can take over if needed.