Haven't had problems navigating my 64Gb stick, even using voice commands works. Here's how my files are organized:
Nothing is dumped into the root folder.
Every artist has their own folder, then inside that the album folders, or if multiple artists the main folder is the album name, all organized by language/genre.
ID3 tags are either as they came from amazon for example, or if I ripped my old CDs using Lame on audacity, I let windows media player or audacity autofill them. Although sometimes I have to pick from more than one album match. WMP automatically applies album images, although sometimes I have to paste in an image directly on WMP.
File names are the song title.
Copy order will make a difference. So make sure your folders and subs are in alphabetical order before copying. If you add folders later they will be dumped to the end. I've used the latter to my advantage in creating sub categories while maintaining alpha order (e.g. all artist folders first then the mixes then soundtracks then instrumental, with each being in alpha order).
No, I didn't do the folder structure specifically for this car, I'm just that OCD. Plus it is pretty fool proof no matter the system it's plugged into, and I've used some pretty old and weird systems through the years.
Folder structure looks like this
Root>English>Artist>Album (like yours it ignores the first folder "English" but then reads subsequent folders)
Hope this helps you.