This looks great so far.
Some ideas.
I wouldn't care if yoy did regional promotions. I'd really like to see a pre-80's legends promotion. A Pure company with a generic World Championship and add some guys like Rikidozan, Lou Thesz, Buddy Rogers, Freddie Blassie maybe, Gorgeous George, etc. I'd freakin' love that.
For Japan
NJPW 80s
NJPW 90s/Modern (I'd put the 90s/modern as one company)
AJPW 80s (if they were popular enough)
AJPW 90s King's Road
NOAH (their current roster hasn't changed all that much, except for a couple, Misawa RIP)
I don't think AJPW is big enough now to have an all-star company.
Maybe a UWF(i), Pancrase, BattlArts hybrid promotion? I'd like that too.
Mexico could have a AAA all-time roster and a CMLL all-star roster.