Jake when it comes to the Win 7 "Libraries" I quickly noticed that actually all they are are pointers to specific folders in the file system, pointers that it is actually very quick to customise. So I simply pointed the Pictures Libraries at the root folder on each of my external hard drives that hold images. The Documents Library points to the My Documents folder by default, and that is where my documents live, although they may be found in subfolders too. So now I just use the Libraries as a quick shortcut to the folders where I want the documents stored. Until I found out by chance that you could add locations of your own to the Libraries I too thought that they were a complete waste of time. I actually rather like the way that Windows Explorer works on Win 7. You have the choice of selecting a library and having all of the files/subfolders in all of "root" directories shown to you at once. Or you can just use the normal tree view on the left, with folder contents on the right, just as you have since at least Win 3.1/Workgroups, which is the earliest version of windows that I have used.
My default action for the insert of CF cards in Win 7 has been to open the LR import window. Usually doing the import direct to LR is what I want to do, I don't have to upload 3000+ images every day.
I haven't really used Win 8 much, so I don't really know much about it, and I have never used Win 10 yet. I am currently getting by on an old Win XP laptop, as my Win 7 system completely died one night, I have a feeling the Win 10 upgrade got on there after all, and killed it mod upgrade. The computer simply fails to boot now. So I can't actually check any of this out for my self at the moment.