You've hit the nail on the head with pretty much every point of critcism. The forum software is indeed old, patchy and probably wasn't intended for Bitcointalk's scale with all the inconveniences and annoyances that comes with those qualities. Hopefully this gets remedied to a degree when the currently in-development new forum software replaces the heavily modified piece of SMF 1.x this forum runs on.
The issues are compounded by the fact that a lot of informational / educational work is being done by the community, instead of the head administrator, theymos. This is both intentional (lack of a concrete list of rules) and unintentional (lack of newbie-friendly info on how the forum functions), in different regards. theymos has mentioned a bunch of ideas on how to ease new users into the forum though AFAIK he hasn't rolled out anything major in that regard. Maybe he's working on it right now or maybe he's saving the effort for the new forum software.
As for the lack of a concrete list of rules, to quote a post of mine:
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There's a reason why the stickied thread of mine still has the word "unofficial" in the title - it isn't officially recognized nor do I expect it to be in the foreseeable future. Just like it was back in the summer of 2014, the "Unofficial list of (official) Bitcointalk.org rules, guidelines, FAQ" thread is a personal project of mine, with the only sorta semi-official support being the fact that former global moderator SaltySpitoon stickied it (IIRC) and that some moderators have stickied translations or links to the thread in the boards they've been assigned to moderate (myself included). theymos has stated (on multiple occasions) that he does not believe in definitive rule lists:
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But I don't believe in having a set of hard rules which is to be applied to all cases. Whenever an argument starts looking like it was written by a lawyer, or relying overmuch on precedent, you've stopped thinking about the real case and have started using rules to retreat into moral and intellectual laziness, divorcing yourself from the decision you're about to make. If you're making a decision about a case, then you're responsible for that case, and you can't say, "I don't agree with it, but I was just enforcing the rules." Every case needs to be handled individually.
- I don't believe in creating definitive rule lists.
So don't expect him to officially link to a page with a list of rules, let alone when said page is a thread maintained by a single moderator.