First, I have to disappoint you a little bit : the skeletons – archers do not have penalties for shooting at night ), so that the latest intensification of necromancers in the patch has made such a site probably second difficulty after 12 Orc Warrior with Lord). Well, it is the lyrics.
Now about question. Exactly one factor( there is some more but this one – 100%) on which depend all the battle – it is game day of the company – the farther away the enemies will be more, regardless of the difficulty level, your party size or the fame.
Surely there are some limits to this? Like im not literally seeing bigger and bigger skeleton sites i think.
Didnt know about skele archers, thats useful info.