Mark Jaquith has published his tongue in cheek version of guidelines that plugin authors should NOT DO or else the plugin would end up being removed. The list is not comprehensive and does not include all situations in which a plugin would be removed but the advice Mark gives at the end of the post should be heeded.
Be cool, think of how your plugin benefits its users, and write awesome plugins.
Also read through the comments, especially for Mark’s take on #5.
Much of this list is complete BS for the following reasons:
1. If this list were accurate then Matt would have to get rid of his plugins from the repository. Think about it don’t Akismet and WordPress stats violate numbers 2 and 7 — two of the most egregious cases you’ve listed above.
2. Where do you fall on freemium plugins then (plugins that provide value in the repository but have a pro upgrade). Should these be removed from the repository just because they charge money for an upgrade. Does this violate requirement #8?
3. What’s wrong with getting credit for your plugin? How are plugin authors supposed to monetize anything if they can’t even insert a couple of links to promote their stuff? If that’s the case then why would anyone ever write a plugin in the first place? They wouldn’t unless they are a 25 year old geek who still lives in his parent’s basement.
So I agree with most of your points — I think that obviously developers should provide value and write awesome plugins. What I don’t agree with is the attitude shared by you and much of the WordPress community — that plugin developers can’t be rewarded for it.
I’ll tell you what — if Matt and the folks at Automattic would spend less time coming up with ridiculous/socialist ideas like “core” plugins and more time figuring out how to make it worth developers’ time and effort to write *and maintain* wordpress plugins then maybe you’d find fewer crappy plugins on the repository.