Many people only think of picture rail as what you find in old Victorian homes, but modern picture rail can be much less obtrusive and lightweight. I have a lot of framed art as well. When I finally bought a house I installed STAS minirail throughout. The "wires" are transparent Perlon filament, and anything you hang can instantly be adjusted vertically and horizontally.

This is way better than arguing with partner about the proper height, making a destructive hole, then having to cover/patch when opinions or artwork change. My walls are not drywall, so that was a big factor, but the freedom to arrange/rearrange is a major benefit.