Agreed, and I miss the old wiki, but wikis don't scale very well to time-sensitive information without even more chaos and management. I do think a lot of our problems do stem from the lack of wiki usage. Wiki search functions range from bad to absolutely terrible, which will bring people right back to posting. I think it'd be far easier to bring this community forward a little more than shift it into a wiki-centric community.

Sub-title fields sound good, but I'm having trouble thinking about what would go in a sub-title that shouldn't just be the first sentence of the post itself: maybe let moderator-types set a subtitle to aid searching?

Along those lines, what about letting thread owners / moderators attach a Wiki link to a thread?

Sorting by thanks is great with that assumption, but as far as I've seen, thanked posts aren't much more useful than unthanked posts in the context of a given thread. Maybe have a TOC sorted by thanks to skip around?

I've got to admit that I've found the thanks function near-useless except where a thread author thanks the person who answered their question. I usually see it used as a "Me too!" button on negative comments. Then again, I'm a heretic who hates 10-page threads, so what do I know?

tl;dr recap:

If the wiki was a great match for how this community works, more people would use it. If the wiki model worked for how our contributors do work, more contributions would be made to it.

Honestly, I think we want something like Instructables long-term. For now, I'll settle for fewer threads.