The Linux Filesystem Hierarchy says that
/media is for
subdirectories which are used as mount points for
removeable media such as floppy disks, cdroms and zip disks.
provided so that the system administrator may temporarily mount a filesystem as needed.
I often find it convenient to have a temporary mounting point
/mnt available, and therefore I don't create any sub-directories or such there.
Internal drives are perhaps not to be considered "removable", but since
/media can hold a bit of everything concerning the mounting department, I use that for internal drives as well.
All of the LFS are just common recommendations and perhaps best practices, so whatever suits you is fine, within reasonable bounds. Personally it suits me best to use
/mnt for very temporary mounts (loopback disc images, foreign USB drives) and
/media for more stable mounts.
Since extra disks today often in practice holds just "media" (movies/music/etc), I find it quite mnemonic as well :-) .
To directly address your points:
The document I linked on the Linux filesystem hierarchy mentions your consideration regarding polluting
Placing the mount points for all removeable media directly in the root directory would potentially result in a large number of extra directories in /.
, which is implied to be something that should be avoided.
See earlier discussion.
Very un-Linux-y in my eyes, but of course it works.
4. "Any path you like"
In practice "yes", but why would one not like to have them mounted in an organized manner?
Regarding mount names, I would also suggest to at least avoid naming them e.g.
/media/sdb1 and so on, since this is not really a partition specific parameter (as UUID already addresses). Personally, I use a combination of a personally assigned ID number and the partition size, such as
/media/5-2000. The partition specific unique ID enables me to tab complete by a single number after
/media/. But this is all discussion on very individual preferences, so I'll stop here.