The logical thing to do, it seems, would be to focus on the shorter, canonical distances and work on closing the gap between my recent times and old PRs. Ie, shoot for a sub-1:40 half this year, or a sub-44:30 10K. Destroying my marathon PR suggests it's entirely possible, and I've got a good, long chunk of time before I need to start thinking about marathon training again. In a way, it's a no brainer--a couple of completely safe, reasonable goals, definitely doable with some work.
And...also completely unmotivating.
It's not that I wouldn't be pleased to run times around my PRs this year; truly, that would be awesome and I would blog the heck out of it. But right now, that's not enough to get me out on the roads more than 20-30 uninspiring miles a week. No matter how hard I try, I just can't get excited about it.
I've been trying to figure out why, and while chatting with a friend one day about my lack of enthusiasm for what should be pretty cool accomplishments, she asked me, "But have you ever thought about shooting for a 1:35 half?"
Of course I was appropriately scandalized by the very thought.