I live in an apartment with a very high ceiling/wall. I'd like to hang a few DIY Rockwool acoustic panels on it to help fill the empty wall space and to cut the reverberation. These panels weigh about 15 lbs each. My initial thought was to get a nice-looking piece of long 1x4 whitewood and run it across the wall with screws going into studs, and use that as a secure hanging point for the panels. However, I want to minimize the number and size of holes I have to repair eventually when I move out.
Supposedly, there are picture hooks/hangers rated for 20 lbs or more (example: https://www.amazon.com/Picture-Hangers-Gallery-Pictures-Painting/dp/B075FC3W9L/). The nails would, in theory, leave smaller holes behind than screws as long the panel does not end up ripping it and a chunk of the drywall out.
So my question is, would a single 20 lb rated picture hook really be safe enough to use in drywall (not a stud) for my 15 lb panel? I would probably use two anyway to be safe and spread the weight, but I'm curious if a single hook really is enough.
The wall (yes, I know the lights aren't centered):
One of the acoustic panels: