Would it be off-topic to have a question where people can showcase good preambles for some specific purpose (like assignments, books, lecture notes, letters, articles etc.)? I am thinking about a topic like Showcase of beautiful typography done in TeX & friends, but where you can show off concrete preambles that are useful for this and that particular purpose (obviously, we would need different questions for each purpose). I am not thinking about a topic like Best practice on organising your preamble, which is more concerned with the theory of overall preamble design. Also, What packages do people load by default in LaTeX? is not what I am thinking of either, since it is for showcasing individual packages, not full preambles. There is currently (as far as I can see) no topic here that matches my suggestion, which might be because it would be considered opinion-based.
I expect a lot of comments arguing that it is impossible to create one preamble that solves all problems, that it is better if people sit down and learn TeX themselves and find out which packages they need. The reality is that many people never learn to write proper TeX at all, precisely because they are left alone in the vast jungle of classes and packages, many of which are obsolete, poorly written, unnecessary, do not work together, or break core functionality. Furthermore, there is an equally outdated collection of manuals on the Internet that promote bad coding practice and wrong solutions. As a result, a lot of people get started on TeX by taking over preambles from others, which are filled with precisely the mentioned kind of packages. For instance, I have found LaTeX preambles on the Internet that still use
In my opinion, a lot of people would benefit from a topic on this page that showed up-to-date, well-written and well-documented preambles, created and maintained by some of the TeX oracles in here. They cannot and should not contain solutions to all problems, but should include the standard packages that many people will need in this particular situation. The usual Stack Exchange voting system would naturally regulate such a topic, the best preambles coming out on top.