use of resources, or wrong decisions about branch/god/gear.

use of resources (too conservative or too liberal) , or wrong decisions 
about branch/god/gear.

games: in the absence of a human moderator, games can either be soft
in the sense that optimal play ensures a win. Apart from puzzles,
though, this means that the game is solved from the outset -- this is
where the lack of a human gamemaster is obvious. Or they can be hard in
the sense explained above. We feel that the latter choice provides much
more fun in the long run.

games: Ideally, a game like this would be really challenging and have 
both random layout and random course of action; yet still be winnable 
with perfect play. This goal seems out of reach. Thus, computer games 
can either be soft in the sense that optimal play ensures a win. Apart 
from puzzles, though, this means that the game is solved from the outset 
-- this is where the lack of a human gamemaster is obvious. Or they can 
be hard in the sense that unavoidable deaths can occur. We feel that the 
latter choice provides much more fun in the long run.
Crawl has a huge number of handmade vaults/maps to tweak the randomness. 
While the placement, and often parts of the contents, of such vaults are 
random as well, they provide several advantages: vaults offer challenges 
that are very hard to get via just random monster and layout generation; 
they may center on some theme, providing additional immersion; finally,
they will often contain some loot, forcing players to decide between 
safety and greed.

or leave it to min-maxers if we feel that the naive approach is good
enough.

(either in the manual, or by in-game feedback) or leave it to min-maxers
if we feel that the naive approach is good enough. 

on their toes by making shallow, or cleared, levels still notr trivial.

on their toes by making shallow, or cleared, levels still not trivial.