Those doors have a "solid" feel to them, so it may be possible to add glass inserts, but why do you want windows into the bathroom, LOL ?
We will probably never use the acordian door and we might just take it out, but a real door there would narrow the hallway a lot when it was open, wouldn't it?
We just took delivery of our Landmark and haven't even slept in it yet, so I'm just imagining the mods you are making.
Keep the ideas coming!