Insulate back of high and low voltage gang boxes in attic
There's no harm in using more insulation than you technically need, and it's cheap. I'd do one of these things:


Hang batts vertically over the wiring; tack them along the top (and maybe at the the bottom depending on what's down there) and let them bulge out over it all. As long as they fit snugly together they'll do a fine job. There cannot be gaps or it does almost nothing.
Frame out an offset wall and move the insulation to that (or just add more and leave the existing). You could leave yourself enough space to get in an do later wiring work.