That's a lot of humans; the Plains will be heavily contested.
I'd suggest 2 human, 1 each of the others, and two random.
On my map, I had much more random terrain, so that all of one type wouldn't be together. Also, that map is huge. It could be a very long time before the realms encounter each other. What's the difference between the two types of trees?
8 hexes is a lot.
IMC the PCs started with two hexes (one Small Town with Garrison, one Thorpe), and have expanded fairly quickly.
Same here. The RAW for large realms are excessively punitive.
I'm DMing, and running the minor NPC realms that they have discovered, and the major NPC realm I put in as a threat. It didn't seem to be really necessary, as the minor NPCs seem to be enough of a threat.
I've been doing a season every week (if nothing much happens, longer if there are several battles to do).
In-game 'week' turns are unnecessary, as nearly everything happens seasonally.
Geoff.