#1
just a simple question:
what classical songs can be used as influence to metal or shredding, maybe pagnini?

if you can tell me the name of the sonata or something please.
#4
Maybe Paganini's "Caprice no. 24". You should try to play the whole piece.
Paganini's "Moto Perpetuo".
Frederic Chopin's "Fantasie Impromptu". That one covers a lot of different techniques.
Some Antonio Vivaldi pieces are good exercises too.

That's all I can think of right now.