I'm trying to tag some audio files, most commonly called OTR (Old Time Radio) but it also applies to stuff like classical music and other audio that can contain lots of metadata.
For example it is not uncommon to have major actors, initial air date, recorded air date, etc. To put it simply there can be a lot of data which simply would not fit in a ID3v1 tag.

Right now I am doing ID3v2 tags in Tag&Rename, and although I find it great for standard music, the standard ID3v2 fields are not sufficient to handle all the metadata.

So I'm looking for suggestions on how to tag these files (methods & programs)

If at all possible I would like a system that would keep ID3v1, ID3v2, & another tagging system in sync so that it would be the most universal to get the metadata on any mp3 player

You may want to take a look at this thread. It is in the works, but we want to come up with examples showing exactly what info should be stored where. Also, the Matroska tagging format offers a little more flexibility and may be more of what you are looking for.

id3v2 offers an involved peoples list in 2.4. Also the id3v2 comments are multi-entry comments, meaning you have multiple headings and info instead of one block of text. Then there is the bio field for background on the radio show and lyrics for the transcript.

I thought with ID3v2.4 & ape you can create your own custom fields?
I will have to look into the matroska system but I think there would be some fields which would not be included.

What programs can display, read & write ID3v2.4 & apev2?