Would it even be possible to survive, at all on a glacier without any items? Or is that a challenge you're guaranteed to have 'fun' doing?
Of course not. This is a strawman that the sandbox crowd drags out when someone points out that the game currently has no challenges: "What do you mean, no challenges? You can make it as impossible as you want! Start with no equipment on a haunted glacier and then run your dwarves around in circles until they die!" Well, duh. That's not a challenge, that's just a self-inflicted game loss.
(And if you hit "Play now" and then abandon the fortress, you lose even faster! Woo hoo! Endless replay value!)
I've been considering whether the goal of well-curved difficulty (in the sense of the game giving you a relatively easy start and then cracking down on you as you progress, rewarding you for taking risks and overcoming obstacles) is fundamentally at odds with the goal of a coherent world simulation. It's certainly easier to generate challenge when a goblin army or a vein of platinum can literally come out of nowhere just because the risk/reward calculation demands it.
Presently, I think the goals
can work together but it requires a really sophisticated simulation. For example, goblin raids. The goblins have to wait a while before attacking you, or you just get wiped out. This is a little weird, because goblins are a scavenger civilization and they'll prey on the weak. The best time for them to attack you, in terms of risk/reward, would be before you even arrive at the site. They knock over a couple of wagons and they get all your starting gear. But if you had a 75% chance of being instakilled by bandits right after the Embark screen, that wouldn't be much fun.[1]
The natural way to make this work is to have them not
notice you until you're a big enough target. That, in turn, requires a world-map "fog of war" that applies to AI civilizations (this is a hard problem--it means they have to make decisions based on incomplete information), along with some kind of knowledge-spreading mechanic that makes big settlements more likely to be discovered than small ones, or the ability to track caravans and find out who they're trading with, or something like that.
Or the simulation can cheat, but Toady has made it pretty clear that he doesn't want the simulation to cheat. So it has to be very smart. Which, so far, is the direction it's headed.
However, I don't think it
can be very smart across all the possible world configurations that players come up with. It needs a sensible stock configuration so that these mechanics can be tested and balanced. It doesn't bother me that you can change the raw files. It does bother me when any concern about game balance is answered with "just change the raw files".
[1] Though once some of the Army Arc stuff is in, it
would make sense to have to protect your expedition on the road if you're going outside the borders of your home civilization. You might need to give your starting dwarves some combat skills, which would be entirely in character for these rugged pioneer types.