Most uses do not have lots of unused devices with no media in them, This is a very rare situation.
I can understand why you don't want to spend time on this issue, although I don't think it is as rare as you think.
Desktop machines with internal flashcard readers are generally installed this way. When the driver is installed for the first time, a different drive letter is assigned to each slot of the flashcard reader. (5 drives in my case).
That said - I'm no longer concerned about the issue because I have discovered a work-around. I'm letting you know in case you receive a similar complaint in the future.
It is well known that you can use the disk manager to reassign drive letters. What seems less well known is that you can assign a device to an empty folder on another disk.
You first have to create the empty folders manually using your file manager.
I used folder names such as "FlashSDmicro" and "FlashSDfull" and "FlashCompact" on my G drive (which I use mostly for backups)
Then you right click on the disk (in disk management) and select the "Change drive letter and paths" option. Then remove the drive letter that is currently assigned. Then click the radio button that allows you to enter a folder name and browse to the empty folder previously created.
It's as simple as that. I don't use flash cards so often that it is worth it to have a drive letter assigned to it anyway. In fact this is somewhat easier since unlike the drive letter, the folder name tells you which slot you are using.
Now I can go back to my preferred side by side panel arrangement which I had abandoned because there were too many drive buttons. And the clutter in the tree view is dramatically reduced. I'm surprised it took me so long to find this solution but it works great!
~Paul