Dungeon Crawl in my opinion is one of the best games ever madeHaving played a lot of both NetHack and Crawl, I think it's pretty bold to claim either game as the "best game ever". Both suffer from the same problem: past a certain point, your character has too many options for every situation and choices become boring and trite.
Crawl tries to "fix" the problem by making a lot of your powerful options unreliable. I believe this is the wrong way to do it. It messes with the player's natural feedback loops by inviting them past a point of no return demarcated by a hidden variable (the random seed governing the unreliable option).
Both games also suffer for the fact that they misuse a food clock. A food clock is a crude mechanism to stop the player from abusing regeneration of health and respawning of monsters. The problem with it is that it's a linear mechanism which simply does not function properly with a nonlinear game. Again, it invites players past a point of no return in cases such as foodless dungeon branches. Crawl tries to "fix" this by giving the player way too much food, but that just lengthens the feedback loop without actually solving the problem. The original Rogue (and its spiritual successor, Brogue) has a working food clock because it's a strictly linear game with a finite amount of food balanced against a finite number of areas to explore.
Both Crawl and NetHack also suffer heavily from the problem of "windshield monsters". Like so many bugs splatting on the windshield, the games lull you into a sense of complacency until inevitably you walk around a corner and something really nasty notices you and you die. Yet another case of a long feedback loop that messes with the player's expectations. This is the game play analogue of jumpscares from the horror genre; a cheap trick that ends up pissing off the player most times.