[johan osterman]

Blood of humans might very well be weaker, most themes are on the cautious side, the idea being that it hurts balance less if an alternative to a nation is weaker then the orginal than it does if it is stronger.

Another point that strengthens you case is that themes that requires a scale setting of the optimum will still recieve income penalties for the scale. So blood of humans are stuck with a -5% income. As is Niefelheim. The idea being that they do not live under optimum conditions for most of the inhabitants, most Jotuns are uncomfortable under the cold preferred by the Niefel Giants etc.