update: i took the problem to my dealer ('16 crosstrek is still under warranty), and the service dept determined that the mechanism, which the lever attaches to, was very loose, and tightening the bolts holding the lever to it didn't accomplish much of anything.
they're ordering a new sub-frame, presumably with a tighter linkage, to replace mine - should have it done this week. downside is that the sub-frame doesn't include any of the trim pieces, cushions, airbags, etc. so they'll have to re-and-re all of it. and i get to spend a couple of hours of quality time in the waiting room... (and then i might have to mcgyver the handle anyway, so it doesn't stick out.)
"more news as it happens..."