If one operates on the goal of "I want somebody to see this, ideally soon, but I don't want it occupying a whole slot of the discussion list for <however long>", then it seems like a reasonable idea to use an open thread which is not nearing expiration. A lot of the stuff posted in OTs is basically personal - stuff that other people are much less likely to care about responses to than you are - and making a new post (even in discussion) feels spammy for that in a way that posting in a OT doesn't.

I personally like the suggestion of having a section just for open threads, where things that people would post as a top-level comment in any given OT can instead be made a top-level post there. It would iterate quickly, of course, but that's not necessarily bad; every top-level would have some time in the limelight.

Alternatively, is there a reason the OTs need to expire? Obviously they run the risk of getting extremely long to load if there are too many comments, but surely that's a problem the codebase can cope with. It already highlights new (posted since your last visit to a thread) comments, including new top-level ones. Is there a way to skip to the first/next new comment in a thread?

Meta question, on the other hand: is the issue of these cyclic waves of OT activity sufficiently problematic to warrant significant changes? (My feeling is yes, but mostly because the cost seems minimal; I guess I don't feel like the issue itself is that severe.)