I use only last names for most composers and add an initial or first name when it is needed to distinguish several composers
Mozart = W.A.
Mozart,L.
Strauss, Josef
Strauss, Johann
Strauss, Johann Jr.
Bach = J.S.
Bach,JC
Bach,CPE
I also use a full name when I would not remember just the last name
Lanner, Josef
Once I use a Composer name, I can pick it from a drop-down list in the tag window. That helps me standardize and avoids mis-spellings.
For performers, I use just the last name if it is unique. For a concerto, I list the soloist, then the conductor and then the orchestra.
Rubinstein
Fleisher_Szell_Cleveland Orchestra
I use a last name first style for work names
Concerto, Piano No. 19
Quartet, String Op. 2 No. 2
I tag movements with a number and a single word when possible
1 - Allegro
4 - Rondo
This limited info is adequate to identify the movement currently playing and to help identify a file if there is a screw-up. It is much quicker to type in than a long movement name.
I'm primarily using tag info to find music files I want to play. I don't try to make the library database a complete reference. So I picked standard forms for tag material that suit my needs. I'd suggest that you think about what you want to do with your library database and make choices that fit your needs.
Bill