Why I got rid of autoscum:
Autoscum is an unnecessary, abusive option.  The supposed reason for
autoscum is to provide better items and dangerous monsters.  Now, I'm
all in favor of more danger and better items.  However, the proper way
to get better items and more dangerous monsters in a well-designed
roguelike game is to dive.  Autoscum, however, is not just unnecessary,
but makes the game easier.  Yes, easier.  With autoscum, more vaults
are generated than normal.  Vaults are *not* balanced against the 
player.  In fact, with a little bit of *destruction*, even the feared
GCV can be looted with very little danger to the player.  Your average 
player does not die in vaults, but rather in the most boring places.  
This is because vaults are obvious to anybody with trap detection,
telepathy, item detection, monster detection, or, of course, magic
mapping.  Because of the design of most vaults, your yield in items
exceeds your chances of dying greatly.  In GCV's, for example, you
get items 40 levels out of depth but monsters are limited to 20
levels out of depth.  Since vaults are anticipated, players have time
to swap in their nether resisting armor, quaff their speed potions,
read a selection from Resistance of Scarabtarices, wield Calris, 
find a tele-away wand, dig antisummoning corridors, etc.