Sock's been working on his own Quake stealth mod, In the Shadows and as a result he's written a few articles on his experiences with getting feedback and creating a single player game. I found them to be a good read.
In the Shadows is still a work in progress, you can learn more about it on Sock's website.
Here are the links to the full articles and excerpts from the introduction of each article:
Do you really want feedback?
When a developer creates something that they feel proud of, it usually involves a large amount of time, energy and emotional investment. It is not uncommon for people to pour their heart and soul into something creative and then feel overly sensitive afterwards when confronted with a stranger's opinion.
Understanding what type of feedback is being offered can help you get past defensive feelings and realize that feedback is about helping to improve something, not hinder it.
Feedback Loops
I think the best way to improve something is through iteration or feedback loops. This is where you collect as much feedback as possible and then refine it down to a small set of points. Feedback can often be wild and crazy, but nevertheless it is an extremely valuable development tool that should not be overlooked.
Exploration is the Key
I like games that have places to explore, mysterious locations to discover and background stories that glues it all together giving me the clues to why it was designed that way. I decided early on in the development of the MOD 'In the Shadows' that I wanted to design small story events that were located off the main path, that the player could choose to explore if they want. The starting area for the MOD is called the Temple of Swords, a dark cavernous location with cold stone walls and many guards looking to show intruders the sharp end of their sword. Like many things in the Quake universe the start of the story event 'The Well of Bones' is when the player finds a Key which is how most modern games mechanics work (PDA, mission update, NPCs) except Quake is more obvious with its choice of props.
Looking Smart
One of the challenges of designing a stealth combat system is that the AI needs to be smart, or probably a better way to put it, the AI needs to look smart! Generally most players will forgive AI doing the odd dumb thing or two in games, but if the AI manages to do something cool or funny before they die then it will be remembered with fondness. The AI don't need to have a GPS strapped to their back, they just need to look like they know where they are going!?!
