The nations favoured by most people are clearly British and Germans, and if you believe the rest of the forums (not just this poll), French/Koreans/Chinese are also favoured nations, albeit a lesser extent.
Why? Because these nations are great for attacking AND have something else that helps the nation grow quicker. Well, except maybe the Germans but their attacking benefit outweighs their lack of 'something else'.
This should be obvious to Nexon. If you want other Nations to be more represented in the player pool, good attacking nations like the Japanese and Greeks should be combined with a better 'something else', something that will help them grow more significantly than their current 'something else'.
I appreciate the idea of the early finish on Greek upgrades but it's not important for me, I can take it or leave it. However, if the amount or %age were more significant I'm sure it would have much more appeal. Same goes for the Japanese. Who cares about longer peace treaties in the grand scheme of things? Or a town centre that shoots at troops one at a time when multiple troops are shooting at it?
People prefer attacking in this game, if the under-represented nations don't have a significant advantage to their attacks, can you at least give them a much better 'something else' ?