Good posts guys, you're all right on many points.
Not being motivated by profit and time constraints does help to make things (here a game) that can be more enjoyable, but it does take longer, usually
Being open source is also a great idea, and many games are incorporating that feature. But you have to be carefull about what you imply by open source. Obviously, the way the UI works is obviously part of the "black box"; can't be changed unless a lot of code is rewritten and recompiled. Ships statistics however are a good subject to be open source: defined in text files.
IMO though, not enough game try to use AI driven by text file. I could be wrong however, since I'm not a modder. I've never seen mods, or very few, that actually made the AI opponents play better. Usually, patches fix the AI. The only game that comes to mind is Hearts of Iron, where units have a weight, and the AI builds its unit based on their relative weight. In a way, that's the matrix I was referring to in my earlier posts.
A piece of advice on your project: the more time you spend on the initial planning and design, the less code you'll have to write, rewrite and rewrite and rewrite...
I know, I know, you probably heard that a gazillion time, but it's true. I'm an IT professional, and projects that fails, meaning overlap in cost and time, are usually due to incomplete requirements.
You should always define a goal. Always. Something like "this game is gonna rock because A, B and C". A simple phrase. Just a concept/idea. And kept it in mind during development. Anytime you're gonna spend time designing and/or coding features, always ask yourself "is this gonna fit in what we're trying to achieve?". If it doesn't, then you probably shouldn't do it.
For instance, like many gamers/programmers, I've had my share of "developing" game on the side. My last project though, I've been writing, writing and rewriting the initial design document over and over. It's about 20 pages now, for the last 3 months. Of course, I only touch this document from time to time, it's a work in progress. And I'm happy I didn't code a thing yet, because I had drastic change during this period. But I'm getting there. Slowly
In my project, my goal is to make a space wargame, with an open-architecture, that has no ressource management and no buildup phase, and where 95% of your time is spent on assembling fleets (I call them task force) and conduct operations (raid, invasion, probe, attack, etc...) against other fleets and sometimes, planets. That's why I call it a wargame, and not a space strategy or even a 4X. There is no eXploration, some eXpand, some eXploit, but definitively a lot of eXterminate
Why am I doing it? Probably for the same reasons as you guys: because it's fun and intellectually challenging. The part I can't wait to work on, as you might have guessed, the AI.
If you guys are interested, I'd be willing to give a hand for that part, or at least give you feedback on your design. It's always good to get feedback from people that have some distance from your work. When it's in your face, sometime you miss the simple things.
Phew, that was a long post, and not surprisingly, it went off topic a little, but hey, it's all good right ?
See...err read you soon !!!