has anyone here had relatively strong and persistent insomnia that they would attribute to an part of the progress of insight?
Not per se, but like you I'm hardly a world class sleeper either.
Just wanted to alert you to something I've just started that I think you may like to try also: I've been doing 20mins or so metta practice lying in bed at night before sleep. It gives me a nice warm fuzzy / snug feeling and seems like good stuff although it's too early to really draw any conclusions yet.
I've also been doing it when I wake up. Usually 40-50mins before everyone else. Rather than lie there reading the Dh0 or letting the mind loose... metta practice is a great way to start the day. (i can't seem to do anapanasati for love nor money first thing, but this I find very easy!)
As you no doubt know, physical exercise is a must if you're restless...