I think a lot of managers would still choose to go in Utopia, but others would go into micronations, and in micronations, 5-10 competing extra users might make a significant difference for the game to be more enjoyable.
This both excites me and worries me. IF it were limited - as you appear to be suggesting - to 5-10 extra users, I could go with that.
An influx of that size wouldn't water down the nation to being what would amount to Utopia.2 - but more than that would start to shift the balance towards being a league with no real national identity (cue someone to discuss the hypocrisy of a non-Japanese person speaking about identity... but we DO identify with Japan!).
http://with-malice.com/ - The half-crazed ramblings of a Lakers fanatic in Japan