> It's rather unlikely that I'm going to continue to do much development about ADOM.

I honestly don't see how you have the time, given real life obligations, JADE and anything else you feel the need or desire to do.

> It would be a shame to let ADOM vanish with time.

I agree. If you pass away before releasing the source code, ADOM will vanish with time unless someone else with access to the source (one of your kids?) has the motivation and interest to release it. The longer you wait to figure out some way of supporting ADOM, the higher the chance is will disappear anyway. Players move on to other things. Players pass away. So far as I can tell, the Nethack community will figure out a way to have players 100 years from now, but I can't imagine any of us will have much luck getting a significant number of our grandchildren to play a game that has not been updated since ...2002?

> The release of the source code might be an alternative.

I only see four alternatives:
1) Give up on everything else and start working on ADOM again. (Don't do this.)
2) Find volunteers or hire people to maintain ADOM. (Managing people takes time and effort. Hiring takes money.)
3) Have someone else rewrite the game from scratch and then somehow maintain it. (Why? Also, unlikely to actually happen. I'd rather write my own game instead.)
4) Release the source code. (Under terms of your choice.)

> But I'm completely undecided if (a) I really want to do that,

Only you can make that decision.
Other people can only speculate about what your exact concerns are at this point.

> (b) I just want to do it to get someone else to fix bugs (he, quite egoistic, isn't it?)

Well, yes and no. Are enough people really going to go through the code to fix all the major bugs? Probably, but I honestly do not know. So, expecting people to tromp through the code to fix bugs is a little egoistic, but if you don't have the time to fix the bugs yourself (and I don't see how you possibly could) having someone else do it is the only way they will get fixed.

Releasing the source code is the best thing that could happen for ADOM and the players of ADOM. It will get bug fixes, UI enhancements and ports. If you still play the original ADOM, this will be good for you too.

> (c) really start a development community for the future of ADOM.

First things first, who is going to manage and maintain the development community? Managing communities is a lot of work. If you don't have the time to maintain ADOM, do you have the time manage those who do? For the sake of your own life and free time, I think you would be looking at either a self maintaining community, or keeping in touch with a few admins as time permits.

> Let's face it... I still would hate to see the "Angband effect" of dozens of variants with all kind of silly stuff...

Would you rather put up with a few silly variants, that are soon forgetten about, or let ADOM more or less fade away with our generation?

> that's just not what I want. But how would another model look like...

I like how ZUN handles derivative works of his Touhou Shooting games. He lays out his wishes in a couple of FAQ questions in his game manual. They roughly translate as:

Q. I want to use the Touhou characters and setting and make a derivative work...
A. Of course, I don't care. There is no need to report anything special to me. However, there are a few criteria your project must meet:
1. Aside from snapshots, you may not use any of the game's internal data.
2. Aside from snapshots, all data must be your original work.
3. You may not do anything that would have a negative impact on the makers of Touhou or other copyright holders.
4. Please list all references in your work. (Recommendation.)
5. Please list your contact information. (Recommendation.)
6. Please do not mess up the names of characters, etc. (Required.)


Q. I want to use screenshots in a strategy guide...
A. Of course, I don't care. I would be happy to hear about this.
If the snapshots meet the following criteria, I don't care.
1. You may not use screenshots of the ending.
2. You may enlarge or shrink pictures, buy you may not change the width/height proportions.
3. You may not modify images if you can not tell that image has been modified.
Changing colors, adding bullets, changing the names of enemy attacks are all not allowed.
*) If you do modify images as a joke, and make it clear that it is joke, it is OK.
4. Cropping, adding labels and arrows are not a problem.

If you can not tell, contact me and I will let you know if what you want to do is OK.
The details are less important than the fact the usage policies exist. Note the "You may not use screenshots of the ending". You can take a screenshot of anything with the home key, but I have never seen ending screenshots posted anywhere. Even the mighty Google didn't find any when I looked. Anyone could post ending screenshots, but nobody does. There are no threats, no burdensome license, just a simple "don't do that". People respect that and don't do it because communities are stronger than licenses.

Touhou is closed source, but commericial derivative works are allowed by the author because that works for him. Hence, there are a lot of commercial derivative works from character key chains to fan games to music videos. That is the Touhou community.

The Angband community encourages variants. What happens? There are a lot of variants. Why? Because community culture is the strongest factor that affects behavior. The ADOM community is not the Angband community, or the Nethack community, or the Touhou community or anything other than the ADOM community. ADOM will not go the path of Angband, especially if you feel strongly about that and let people know how you feel about it.

How should you release the source code? Just release it with a list of "do"s and "do not"s. Your community is very sensitive to your wishes and this will not change if you release the source code to ADOM. People will respect your wishes for the most part. Those who do not will get a bad rap and their modifications/variants be rejected and disappear. Then everyone will forget about playing them and go back to playing ADOM as you intend it to be played.