Closets and Home Organization - Fixing up or Replacing Sliding closet doors

Our new home has floor to ceiling sliding doors for closets in almost every room. What is the best idea for fixing up or replacing these? They are heavy and difficult to slide at the moment. The closets are fairly deep and can store a massive amount of stuff with the help of a stepladder o reach the upper shelving...

This is a 1950's house, so I suppose sliding closets were a 1950's fad? I haven't seen them on any houses of recent vintage...anyone out there a fan of sliding closet doors?

Mirrored bypass doors are quite popular now. Before you plan on removing these doors, have you tried lubricating the wheels and adjusting them for a smoother movement?
You have an oddity, in that you have complete access to the entire closet with the door open. To retrofit to a modern door, you would have to install a header and recase the opening to 80 1/2", which would entail sheetrock work as well.

I also have bought a 1950's house with the sliding doors. Mine slide quite nicely though and I like the mechanics of them but they are large and boring. I am looking for a way to spice the look of them up. I am afraid if I put some kind of molding on them it will get knocked off when they bypass one another. Anyone got any ideas on how to make them look better. Mine are wood color now but I plan to paint all the woodwork in the house since it isn't anything special. Any suggestions would be appreciated.