Well, to be honest, I've never played a King's Quest game, though I have heard them praised many times, so I'd expect to enjoy them myself. I was always more of a Space Quest and Monkey Island guy.
Space Quest has on occasion been guilty of some of the things you mentioned I guess, to some extent - though never as unforgiving as, say, Police Quest (now there's a game I haven't thought of in years!!). There was one game, early in the series, where the first area had a missable item that you needed much later: a keycode or something. The Guys from Andromeda actually got asked about that in their AMA. I forget what they said, but they definitely weren't defending themselves. That sort of stuff is old hat now.
BUT, they learned their lesson. I don't think any of the later games had any true missables. And they definitely didn't have items that you could "lose" or "consume" before you needed them.
The series definitely evolved towards something more similar to Monkey Island, in which there really was never any way to get perma-stuck (except in Space Quest you could at least die... in fact, the death sequences were often among the more entertaining parts of the game).
Not having enough clues or the ability to work out puzzles based on available information was a problem in a few games, notable SQVI, but that was almost entirely because one of the two creators left in the middle of the game's development.
Now that we're out of the mid-90's, I think developers are a lot more savvy, and I'd be absolutely shocked if it were possible in SpaceVenture to screw yourself over bad enough to need to restart from the beginning. I feel like the genre has really worked itself out of kinks like that. Monkey Island is one series that got it right from the start, and I have no doubt this one will follow their lead in that regard.
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bokonon get your sense-making the **** out of this topic now - Cat1001
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