During level advancement, there are currently options for characters to increase their damage per attack (at +1) or their capacity. Terri made a good point that this is not well balanced, given that the capacity increase is fixed at +1 per advancement chance, but the damage is a bonus that applies for any successful attack, so players will likely only choose to increase damage since it has an obvious advantage. I agree, and in the updates we roll out I am going to change this advancement bonus.
Players should feel free to implement this change now:
+1 to Damage/attack
OR
+1 to Capacity/level.
Increasing the capacity per level I think helps balance this out a bit better. Let me know what you think!