I am not sure if the analysis of an ecosystem translates properly. Nations do not fill niches, they are all directly competitive by nature. There is no possibility for one to flourish without impacting the others.
Sure, you will see less light infantry perhaps, but with a relative balance between resources and income, people will tend to build armies in the way that is most effective, not the most pleasing. That is to say that while it may be attractive to only build your strongest elite unit, if you don't have any actual cheap chaff, then the enemy's mages will kill your expensive troops first.
Certain nations will still favor Productivity. There is still a balance between gold/resources, so high resource nations will still compete in troop count with low resource nations. It think the only thing that will lose relevance is Luck, as it fails to scale according to income levels.
Anyway, how did you know I was going to go with a Mentok pretender?
