I do not want any essays deleted unless there is a request from someone's teacher, nor would I want a system where essays are marked over personal messages - both so other users can benefit from the feedback.
Exactly, I'm not marking essays for that one particularly person, well primarily yes, but as well to help the community.
I learned a lot from essays of other people and I admit, of course I copied some nice sentence starters and similar stuff and used them in my essays, but why shouldn't you? The forum is there to help everybody and if someone posts a question in the math section or an essay in the work-submission thread the whole community should benifit rather than only one person.
It would help everybody by a great extent of you post all your essays up and read those of others, including the criticism by other AN-members. Of course for a SAC you shouldn't really post the essay up since it is kinda unfair towards the other people in your cohort, but generally I don't really count reading and copying bits and pieces as plagiarism.
Deleting your essay after getting it marked by an AN-member is bullshit.