1. Multiple soloists is a tough one. Do a search for classical music tagging in this forum. Others have posted suggestions before. Most involve using custom tags.
In the artist field, I use: Orchestra/Conductor/Solist(s)
Phydeaux creates the following custom fields:
Orchestra, Conductor, Soloist(s), Choir, Movement, Key Signature, Opus, and Year Composed
His artist field is: Orchestra/Solist/Conductor
Ideally, I'd want a relational database so I could associate multiple solists with one file. But that's beyond the scope of a program like this. And is it really worth all the time it would take to perfect it?
2) Its all in the sequence you use for creating the tags. I do it in the following order:
a. Rip the CD
b. Fill in the tags and album art through one of the online lookup programs
c. Make the manual changes necessary to album, etc.
Most of the classcial album art is available at
www.allclassical.com. Usually, I locate the art there, save it locally, then import it into the files. I store album art inside the file. Others argue in favor of saving it in the folder instead.
3)
a. So the files can be read by other players: My car's CD/CD-R player, portables, etc.
b. Also, my general philosophy for software (which comes from many years of implementing software for fortune 500 companies): use off-the-shelf and industry standard programs or formats whenever possible. Otherwise, you add to your maintenance costs and lock yourself into your custom code.