Armies of Middle Earth during WotR

[Kuruharan]

How do you reconcile such tiny numbers of dwarves with the statement that they had grown "strong" again? The population of the dwarves may only grow slowly, but it still capable of growth. Durin's Folk had been mighty enough to provide the bulk of the forces that fought a victorious war against the orcs when they didn't have a settled capital. Why the presumption that they wouldn't be able to field a substantial force when they did have a settled capital?

Upon what are you basing the belief that Erebor would not be able to accommodate substantial numbers of refugees as well as substantial forces in the event of a siege? I suspect that if nothing else the physical size of the dwarven city in the mountain was probably greater than Dale, if not substantially larger (I think it was probably substantially larger). Why couldn't the dwarves have accommodated large numbers of Bardings in their hour of need?

Easterling Theorizing:

I think that given the largely unmitigated flatness of the areas of Rhun, which are visible on the map, that many of the Easterlings were horsey lots and their army composition would reflect that. I picture something along the lines of a steppe culture and army.