These are certainly some of the major wishlist items for the quiz, so it would be wonderful if someone has the time to solve in a way that is compatible with the rest of the quiz module.
The normal procedure for someone doing a major change like this is:
1. Write a document, linked from http://docs.moodle.org/en/Development:Developer_notes
a. The requirements - that is, it specifies what the proposed change is meant to achieve in language a teacher or administrator might understand.
b. The propsed design - how you plan to modify Moodle to achieve this aim, including any changed to the database
, code and user-interface, in language another developer would understand.
this document should be as short and easy to read as possible, consistent with containing enough detail.
2. Start a thread here, or in the General Developer Forum (whichever seems more appropriate) to discuss the merits of the plan.
3. Based on the discussion, improve the plan until a consensus is achieved.
4. File issues in the tracker
for each part of the work - perhaps one top-level issues with sub-tasks.
5. Write the code following all the Moodle coding guidelines
, and attach it as patches to the tracker issues for review.
6. Respond to the reveiw comments by improving the code until it is good enough to be checked in.
Three recent and successful examples of this have been http://docs.moodle.org/en/Development:Plan_to_Improve_Flexibility_of_Question_Category_Sharing_and_Permissions
What I found particularly interesting, as a participant in at least steps 2 and 3 of these examples, was that in the process of discussing the details of the proposals with other developers, we collectively came up with solutions that where better than anything I could have come up with thinking about the problem on my own. In particular, this amazing 100+ post thread
, between Jamie, me, and others, which started off with an idea of mine that turned out to be totally wrong, and ended up with a technically solid plan that lead to the new question bank in Moodle 1.9.
But note that discussion took about a month - time well spent, but a lot of time. And for anyone intersted in bidding for any of this work, note that Jamie, an experience Moodle developer, originally estimated 4 weeks for this work, and it ended up being at least double that. The quiz code has been around for over 5 years, and many different people have contributed to it. In places that shows. Some corners of the quiz code are rather messy and hard to work with. Of course as you study the code in detail to make changes, it is a good time to do some cleaning up. Certainly, Jamie cleaned up large chunks of the code while rewriting the question bank, which I am very grateful for.
There was a thread in this forum some months ago in which someone gave a remarkably small amound of code that implemented auto-save. Regrettably, I have not had the time to investigate it yet. If other people have time to look at it, try it, and tell me whether it works, then that would be great, and let us decide sooner whether (or not) it should be incorporated into the official Moodle release.
Also, you are almost cetainly right, that negative scoreing and adaptive mode need to be mutually exclusive. Indeed, if Tony Gardner-Medwin's plan for certainly-based marking in Moodle comes off, it will may end up being three mutually-exclusive options, since CBM uses negative scores in yet another way.