How to organize a large number of content files

[rme]

I've got a bunch of content (hence I decided to
buy a new, smart TV, build a media server machine and
install a media server package (I pick UMS as you might
have inferred).
So, I've got some:
100 of 'mkv|mp4|avi' movies
1000s of cbr comics
1000s of jpg photos
10000s of jpg images
1000s of mp3 audio files

How to I organized all the content in the file system?
How does it all get displayed? I assume that there is
some trade off between breath vs depth of the file
systems and how it gets mapped into what is displayed on the TV.
Does UMS scan all of the content root directories each time
you start it or does it store the discovered metadata and link
in some persistent data file?
Can UMS use a database as its store?
I notice that some folks use XBMC to extract and store
the metadata and then use a UMS plugin to connect.
Is XBMC better (richer) at uncovering the metadata?
Is XBMC better (faster) at scanning for metadata?
Is XBMC better (database like mysql or mariadb) at storing the metadata?

I am sure that I'll have more questions, but I want to simply
start by choosing the right on disk organization for my content files.

Thanks

[SharkHunter]

UMS "scans" the files as you go along in the file tree. More files/dir longer time to display (of course). You can make use of a database cache which makes browsing slower the first time but then UMS will remember your files (and thumbs it generated).

You can make an offline scan as well (as all other media servers do) which essentially scans all your files and build the db/cache once and for all. This will take ages and should probably be done overnight.

As for depth this depends on your render. If you use a PS3 or XBOX they have a depth limit of 8 (yes silly). UMS has a a built in workaround for that but it will be much "clicking" and if you can sort your files smarter than much will be gained.