I can see few issues with this that wouldn't work with me:
1) How do you deal with songs that have multiple genres?
It is a standard part of the TCON (content type / genre tag) to separate multiple values through either coma, slash.
For example this allows you to select songs that are tagged as both 'Ambient' and 'Rock'.
2) how do you deal with album that has songs of varying styles?
For example: "Prodigy - Music for Jilted Generation" has a dance track like "Voodoo People", and a chillout track "3 Kilos"
http://www.last.fm/music/The+Prodigy/_/Voodoo+People/+tags
http://www.last.fm/music/The+Prodigy/_/The+Narcotic+Suite:+3...
3) Compilations
Let's say we have a compilation made by a group called 'Air'. This compilation is called 'Deck Safari'. Do you use Album Artist instead of artist if it is a compilations (aka: if TCMP flag exists, use TPE2 instead of TPE1?)
Checkout the album:
http://www.discogs.com/AIR-Deck-Safari-Part-1/release/215068
4) I don't understand how you handle singles.
Let's say you have a single ""Wamdue Project – King Of My Castle"" released in 1999 by Urban (563 891-2). Your formatting doesn't store album at all?
http://www.discogs.com/Wamdue-Project-King-Of-My-Castle/rele...
And then, how do you combine it with the fact that a year later was a different mix released by Avex Asia Ltd. (AVTCDS-235) with different set of songs?
http://www.discogs.com/Wamdue-Project-King-Of-My-Castle/rele...
To me it looks like your singles folder is intended for random songs, not to handle actual CDS/CDM style singles.