Hmm. Now who/what for you make your collection? For listening/browsing yourself or for iTunes-fans? I think is good enough to find out and use consequently any simple and clear way to order your substance, and there is a more than good tool to reorganize anytime, if necessary.
Other hand I think that is not a good idea to store any data in that place, where it is not needed for the convenient use (pics, lyrics in musicfiles...). The best way (for/by me) to organize in directories, filenames with care on conventions of possible target platforms, and use tags (what also readable with anytag in Total Cmd or mostly in Explorer) to store more precise, detailed information on most intresting names, titles, dates, for the ability to identify the content of a musicfile anytime. By this style you can store in that directories at any level any kind of so detailed informations and as many as you want, over-hyper-metadata relative to your stuff (full list of staff, covers, photos, disco/biographies, articles; also errorchecking codes; etc.), and it's kept organized; if you are ingenious you can do that like a realy database, without indifferent but huge data embodied in the container really made for music.
Naming conventions? Be as short as possible, don't write redundant or indifferent data, don't use undecodable codes, acronimes, replace characters only when necessary (e.g. not so nice to use dots instead of spaces). Something like this, but mostly you will read your codes...
And so on, which bitrate is in fashion? Doesn't meter. Depends on fileformat, codec, environment, the listening target: as you like; the ear what you usually use to listening music, is yours -- you must know the way of use.