I am looking at "Masonite" brand to replace my sliding glass closet doors with sliding paneled doors - (growing up in a house with solid wood doors, I loathe the hollow core too; masonite has options for core filling that make it look, feel, and soundproof more like solid). Honestly I like having the mirrors and have seen another brand on Houzz with framed glass panels that I might opt for (though there was no distributor in my area). You may seek out the door professional in the local big box store for options and/or the higher end building supply houses that allow retail customers. Good Luck.

P.S. I LOVE the barn like doors on external tracts on the wall, but sadly don't have space/layout to accommodate. That might be an option for you.

Sorry I am just getting back to you! Thanks so much for your advice - love the idea!

Louvered doors get so dusty! And if/when you want to change them they are hard to paint/refinish.

If your existing doors are in decent shape can you refinish them to make them more your style? I liked the idea of filling them so they don't feel so hollow...but even external treatments could be good. Paint? Refacing (veneer or foil)? Fabric or wallpaper? Mirrors? A custom mural (there are lots of places that will make them to your specifications)?

If you can make a cosmetic change that isn't too expensive then you will he at least a few more years out of the existing doors.

Custom built doors would be great, of course, if your budget stretches that far.