Thanks, both!
You might want to run some maths on likely VP scores. If the lizards get less VPs for human bodies than dwarf ones, and there are far fewer humans than dwarves, this may be a bit irrelevant.
Also do the VPs need to balance between the sides? Or does the overall game victory count first, then the player VPs?
Overall I really like the ideas, just want to make sure there is a degree of balance so all players feel they are in with a chance.
These are really good points - thanks! What I'm planning is to take one warband (probably the dwarfs) and work out its victory conditions, and then mirror those with the others. So, for the dwarfs, it might be something like this:
Drive the orcs from the field: 5
Vargram is killed ... 1 point ... by a dwarf ... 2 points ... by Karak Proudcrest ... 3 points (whichever number applies - not cumulative)
Regain the Arkenstone: 3
Other treasure secured: 1 per item, to a maximum of 4.
So that gives a maximum total of 15 victory points.
For the lizardmen, it might be something like this:
Drive the orcs from the field: 5
Each dwarf killed, if the surviving lizardmen outnumber the surviving dwarfs, to a maximum of 4
At least one human killed: 1
Treasure secured: 1 per item, to a maximum of 5.
Again, that gives a maximum score of 15. I'll probably divide the conditions into "battle points" and "treasure points". The difference will be that you need to have some surviving troops to earn treasure points. In the examples above, driving the orcs from the field earns battle points, as does the killing of Vargram. So the dwarfs are a bit more set up for a heroic narrative in which they might all perish, while the lizardmen need survivors to gain the overall victory.
One potential outcome might be that the orcs loot all the treasure (fleeing off the table with it), but lose the battle. In that scenario, the dwarfs could win outright if Vargram meets his well-deserved end.
I suspect each orc leader will gain a victory point or two by simply surviving the battle - no heroic deaths for them if they can help it!