As a run newbie but with decent awareness of ITA and other tools for finding routes and prices I'd find an enlarged section at the start of the thread on what things are likely to help someone find a good TP run. Or maybe this could become a new 'Masterclass' thread that wouldn't be year specific. Many / all of the techniques would remain valid until changes to BAEC that (for example) changed the benefit of 2000+ mile segments so the thread would just roll from one year to the next.

As I touched upon in the TP thread itself things like...

1) When is a good time to book, in terms of things like during a BA / AA / etc sale; about N months before your run because of XYZ; after ABC holiday period in region X; etc.
2) Why some routes offer good value, and how might that be applied to other routes. For example, airline XX is competing with YY in a region and want to drive traffic through their hub or segment ABC-DEF often has lots of excess capacity.

Re your abc list I think...
a) I agree with having one or more threads that focus on factual pieces that could be used to build runs, but not too much discussion about specific journeys that are being scheduled. So sales, unusually good fare routes, gotchas relating to them, etc.
b) I probably see this one as a place where people report specific trips they have planned, either for information or discussion. Maybe that is the main part of the current thread? BTW, I don't understand the reference to 'expired' - why not current as well?
c) Isn't that better handled elsewhere, such as city or hotel loyalty boards?