Load Leagues or Load players, very confused

Ive been reading threads about this and basically I am more confused than I was before. I would like to have as many players/staff in my game as possible. I usually only load England and Spain leagues while I have players from Brazil, Italy, Argentina, France, Germany, and Portuagal loaded.

One of the things that confuses me, is which option is better leagues or players? I read that if you load players over a period of time your game becomes unbalanced the example that was used was if you load players from Scotland and Ireland, somewhere down the line players coming from these countries would be better than say from Italy, if you didnt have it loaded.

If you load a league, I know you would get those players and staff but doesnt that slow down your processing of the game? If I would only choose the leagues as viewable, would all the players and staff still be laoded?? As I said, I am VERY confused on what is the better option

If I decide to load the players, what are the best nations to load?? I know the ones I mentioned above but are there any other that would be beneficial??

Im asking for any opinions or thoughts on this. Im trying to start my first long term game, I usually get bored qucikly, and I want to load the best options. Im going to keep England and Spain as the main leagues, thats all I know right now.

I appreciate any help

You've got all your facts correct. It depends on your computer of course; what you could do is load a small or medium database, minimum leagues (such as the 2 you mention), + a DDT file for all players/staff from many countries. This gives you regen variety and doesn't imbalance a long-term game. It won't slow the game too much since you don't have many leagues to process.