Yeah, next thing you know Uncharted 3 will have random generated levels =). Worms is a good example for a "sandbox" game, you might end up with maps that have 1 team severly disadvantaged.
I reference WORMS because players could create custom maps. eg. We built maps that were complete caverns, and you had to use tunneling skills. That was a completely different experience to the standard artillary mode. Likewise cavern levels meant shifting focus to rope skills and close-quarters combat. All a massive advance on the standard gameplay, and all made possible by simply opening the engine up a little. And I wouldn't expect that from a typicla game like U2. Only the settings.
Noone complains if he has to "hack" (ie. has to go outside the game) or just doesnt do it. If you however have those sliders easily accessible in the game and you end up creating a horrible mess easily by adjusting - then people will complain about a useless feature.
Do people complain about features they don't use? I can understand complaining about features you use that are broken, or want and aren't present. I can understand people complaining about gameplay that deviates from their ideal ("The shooting is unrealistic and I want 2 shot kills." "The shooting is too hard and I want to be able to take more shots rather than just get killed with a lucky hit."). However, I can't understand why anyone would complain about a feature they have no interest in using and do not use!
You said yourself you would like the ability to skip levels if your values end up messing up the game
Not quite. I was not saying that I would set up the game to try and play it wiht some settings, and then when I 'broke' it, would want to skip the 'broken' parts. I was saying I'd like the opportunity to try out different settings in different parts of the game, and the ability to access those parts of the game without having to play all the way through to them would facilitate that.
Letting the player skip the levels. If you just want to replay them , beat the game once and unlock Chapter Select option. What you're asking for is way different than replaying them.
1) Who says you have to have chapter skip from first play? By all means have it as an unlockable feature if you want.
2) Some games have horrible levels that you'd just rather skip. eg. Baldur's Gate Dark Alliance 2 had a dismally dull zombie laboratory level. If I could have skipped that I would have. Now the nature of that game precludes it, but something like U2 would accomodate that nicely. There are also plenty of gamers who aren't particularly good at games, who find some bits challenging. Isn't it better to let them skip a tricky part, or tune the game to their abilities, rather than have them get frustrated and give up, never completing the game and missing a large part of the developers work?
Let me ask a straight quesion - why do you think it's wrong to allow level skip? Who is suffering or...whatever, to make it a bad thing to offer, either as an unlockable or as a first-start feature?