1) Medium, 1.2.4
2) 6
3) Couldn't be clearer
4) Good
5) Composition of the front rank required a lot of thought every turn; the key is to keep inflicting all the damage you can, subject to having a solid front rank at turn's end. Because dwarves, esp. dwarven stalwarts, are key to this, the short movement of dwarves means you can easily find you don't have the unit you want available to plug a hole.
The start is quite tricky - the enemy recruit 4 keeps full of stuff immediately, which makes the player's keep look pretty small; just getting a tenable line of troops from the river to the camp in place before the enemy hit in force is tricky. By turn 6 or 7, the unlimited flow of troops from your camp, plus levelling up of units already deployed, gets you to the point where the enemy aren't going to break through.
The other risk of losing is Kalenz again, the bane of my campaign; as he doesn't have leadership, but has a very good ranged attack, he's too good not to put in the front line, and not tough enough to be completely sure he won't get killed. E.g. making the first line from river to camp you are almost certainly using Kalenz as the dwarves won't reach the river fast enough.
6) 7 - a fun complex field battle.
7) It's a pity the river can't be brought into it more; I wanted a last chance to use my mermen, but the AI chose to try outflanking in the north instead, so my mermen ended up making land forays to use their storm tridents. That's probably my strategy that needs tuning, not the level.
The enemy wash up like a tide, and then ebb away once their strength is spent. It would be good to contrive a way to give them a second wind (excuse the mixed metaphores); maybe have some of Ashevere's gold from the villages held back &released around turn 10 or 12. Or have one of her armies off "fighting the clans" return mid-battle.
In return, I'd like 1 extra square in the player's keep, so I'm not so outpaced by their recruitment in the early turns.
8 ) start gold ~1550