I think I've really nailed down the root cause of my issue. My swing has been lengthening, for the worse, not better. I've always played from a pretty compact backswing, but my increased level of activity lately, combined with more golf, has got me taking the club too far back. I've always exhibited some EE, so this extra "time" to square the club has me completely ahead of impact. I started forcing a 2/3 backswing, and contact/flight was so much better once again, without having to manipulate anything. I've gotta keep an image of Jon Rahm in mind when things get hairy.
This could also explain why I sometimes lose connection late in a round, as my muscles & ligaments have fully warmed up and are allowing my body to rotate and enter way too deep into the backswing.