Region: Atlantian Oceania
I'll always maintain that as long as you can justify it with 'evidence' in your roleplayed background and history then, as long as it's not vastly different to your issues choices and the distorted version that ns.net shows, then you can get away with it.
Take Starblaydia, for instance, as that's the only nation I have accurate RP history details on, of course. I would say Starblaydia is a creative powerhouse - the popularity of ediraf designs, for instance, implied that the nation itself is a stylish, design-led and creative place. The fact Uranium Mining has been my dominant industry since day one means we're a) good miners, b) have nuclear power expertise and c) probably have/build a boatload of nuclear weapons, which also means the science base is fairly high. Our militaristic background is there for all to see (as with most nations), as is the code of honour that goes with it. That then leads into the sporting aspect of fair play as a national characteristic.
Throw in the business acumen, e.g. when Orcinus Vodka was the most famous/promoted/popular spirit on the forums, and you can say "yes, Starblaydia is a rich nation because of all these things..." and not just "because I say so".
I guess the secret is always show your working.