Hmm, I'd like to step in and point out...
Actually, for many of Roberta's more compelling ideas, technology was a hindrence. They couldn't get the game engine they wanted). The engine they were basing much of their early ideas on, was one that was being designed third party by Dynamix (and switched to some other engine as a quick fix). Dynamix was taking too long to finish it. The game engine they forced into using couldn't handle certain ideas like underwater, or water based physics like currents. The powers that be that owned the game didn't want to raise the budget, or extend the development time any longer (it was apparently already over budget and had been given an extra year of developing time). So when they talk about too many people cooking the pot, this is partly to do with the fact that half of the KQ8 team were over at Dynamix, and the other half was at Sierra. One hand didn't know what the other hand was doing! Add to the fact that there was a third group, the Sierra's new owners (the suits) over in France (and the new Sierra president in their pocket), that were pushing for the game's quick release, due to budget concerns, and time (forcing other changes), not listening to Ken or Roberta's advice. So truly there were too many cooks in the kitchen!
Many of Roberta's ideas were added back in the game when she reasserted control in the last year. But they were modified somewhat. Characters were merged, or replaced with alternative characters (that didn't exist in the earliest design concepts). The hermit (with knowledge of all things about the Mask of Eternity), and its crystal of truth (or whatver it was called) for example was split into the Wizard and the hermit in the Realm of the Gnomes. So the final game got two characters for one in that instance. The wood nymph and his sprites got modified into the will of the whisps and King Mudge.
Some of the enemies that were cut, were simply that enemies, to be killed rather defeated through puzzle solutions. The Leprechaun/Red Hat Goblin were both the same character, but they couldn't decide what they wanted that boss to be. It ended up being turned into the Spriggan with the armor (according to Mark Seibert)! At least with the Red Hat Goblin version of that character, some speculate that the player might have encountered more than once through the game (although this hasn't been confirmed).
No one really knows what her plans were for individual puzzles, although few of the behind the scenes information and interviews suggests even more physic based/ action based puzzles, as opposed to classic style inventory puzzles. Especially in the cut underwater level!
The witch would have had a more introductory sequence leading you into her tower, before she changed forms, and started the boss battle! It's not a puzzle, but it would have been a more compelling introduction (this is truly missed).
Castle Daventry may have been extended, not for puzzle purposes, but simply for setting the scenery (would have given a few more places to explore). Giving you a better idea how much damage 'the cataclysm' had caused on the kingdom. You could have gone into the bedroom of Rosella for example!
I think the thing lost that would have improved the game probably the most, is the loss of a compelling ending sequence! It's hinted at by the Oracle of the Tree, but never realized in the released game. That is Connnor was to return to Daventry, and meet King Graham. The torch may haven been passed (Connor becoming the knight of Daventry, that Graham used to be)!
Some ideas were changed simply due to evolution of the story. Connor went from being a nameless statue, to a fisherman's son (Connor mac Lyrr), finally to the tanner (Connor of Daventry) he was in the final release. The exact timing of these changes were made is unclear. The statue idea goes back as far as 1995 or so (when she was first talking about the 3-d "Doom" KQ, someone mentioned above).
BTW, I love KQ8, if anyone wants to know more, I've been putting together a behind the scenes development history of the game (as well as other games) over on the King's Quest Omnipedia.
Most are probably surprised to learn, that nearly each game in the series, had alot of early ideas, that were cut for various reasons. Budget concerns, lack of time in the development cycle, or technology limitations. Quite a few ideas that were going to be in the original KQ1, ended up going into KQ2 for example!
KQ7 also lost quite a few things before its release, including at least one or two other areas. As well as a longer ending sequence, and several encounters. Many of these things can be found in the game's files!
There were a handful of things completely changed or removed from KQ5 as well!
Rarely have we received the games as the developers had initially envisioned!
For more see here;
My point is, Sierra would have done better if continuing with Ken at the helm.
I'd be careful with proclamation. Ken has been on record of admitting had he still owned the company he would have done away with adventure games, went more towards console style action/arcade games, and more productivity software. He was starting to believe that he needed to emulate what was becoming popular out there and less risk taking to make his company more successful and money making.
I recommend checking out his editorials in the later Interaction magazines for examples. Success was going to his head. It was that success that made him forget what truly made them successful. It was that success that lead the mistake of selling off the company as well. He was literally transforming into one of the Suits that plagued the company in it's final years.