^_^ They like the random aspect of the d100 roll, so I've just capped it at 50 minimum for them.
I've also been granting them physical soul object item drops (Soul of an Unknown Undead, etc) that they can use to get 2d100 souls each, so I'll probably also just sprinkle a few more of those into the loot.
The absolutely tight mechanics of this are really awesome though - love the equipment based play and the trade off between weight, defense and speed!
Been using loot and extra spells from Grave just for a bit more content - we liked it so much we're doing a second session this weekend! Woot!