Well, again I blame myself to start a discussion with you, because it's usually neverending story.
Just think, even if people can sign up in different country when will they do that? When they sing up or after few season of playing? In first case, new users don't know situation in the game. They don't anything about BB especially about timezones and boxscore's delays. So let's say random European usually will sign up in his own country. After few weeks/months it will be a little annoying for him to wait to see boxscore. But your idea didn't consider such a situation, that's why I wrote a point
"you assume both things:
- new player already know BB's habits (he should know where to sign up) or he was banned, so he knows where to sign up"
In second case (possible country change after few seasons of playing), you will lose all your assets. You will start from the begginning...again. That could be frustrating and probably no one will decide to do such a thing just for earlier boxscores.
I already point out your first suggestion, where you wrote to play matches in different timezones in a league.
Another counterargument, If you let people change their country, probably people from micronations will move to bigger countries rather than bigger countries -> micronations. How many posts did you write about lack of competitiveness in micronations?