Just wanted to note that 0.915 is the first patch where the challenging AI felt, well, challenging. Eventually abandoned the game after getting my ass handed to me by the combined forces of Gilden and Pariden, fighting on two fronts; my next game will be on normal.

A few other comments:

• Monster power seems spot on. With dense monster population and a lucky early sand golem, Verga was able to clear a significant area from early bandits and critters, while avoiding the scattered drakes and shrill lords easily enough, before eventually hitting a wall of hoarders on the border of shadowlands, halting his exploratory campaign. Plenty of space for expansion, and the lair spawns (lots of four-flavoured shrills and baby drakes, plus one group of river skaths) were challenging, but not overpowering; I was able to hold them off with a stationed low level champ plus some trained units to supplement the city militia, although I reckon leaving the city with nothing but militia would not have been enough until at least city level 3. That seems like a good balance. Only once did I make a mistake of building an outpost within range of an earth elemental's sanctum, sending him on a mini-rampage raising everything in sight for 20 turns before eventually returning to his lair.
  
  
• Really missed strategic zones of control. My frontier city had a hill to the south with a single-tile passage on the other side of the hill, just outside my area of influence, leading into the depths of my territory. Gilden scouts figured out how to repeatedly abuse this passage to sabotage my core infrastructure, forcing me to chase them all over the map (good on them!). Eventually, I parked a minor army (a handful of warriors and a juggernaut) on top of the hill in an attempt to put a stop to this madness; yet the scouts, with their movement superiority, easily waltzed past my army and continued on their merry path of destruction before the juggernaut could even put his pants on. Something as simple as the tactical ZoC implementation -- army loses all remaining actions when moving past an enemy army at war -- would do wonders to the strategic depth.
  
  Also, sneaking past a monster army to clear out their lair while they are not looking feels very cheesy; strategic ZoC will make me think twice before attempting this.
  
  
• Every single Gilden army I fought included one caravan and one pioneer.