Another issue / suggestion 

I noticed another issue that I guess it's not listed anywhere: when some articles start getting big and full of information, wikipedia users refrain from deleting weak or even nonsense parts. They believe it's good to keep all that (useless?) stuff, probably reasoning that some information is better than none. That's why many many articles get huge and are tagged to need the attention of an expert (who would hopefully clean up all the junk).

I strongly disagree with this behavior of keeping junk on the main page. I guess the editing system should allow two versions of an article: the main one, with the information that was agreed by everyone (intersection of information) and another, longer one with all the possible information for that subject (union of information). In this way people would not be so afraid of deleting junk because it would be stored on the second page, and the main article would always be a cleaned up version, which, if not complete, at least would not fail on quality.