2. Don't bother. You can but it's not safe.
3. Don't upgrade the guitar for now. The one you have is pretty decent. You could change the pups if the ones you have are stock. Most of the music you play does not require a trem, and also varies in the tunings used. FR is a no-no for varied tunings.
4. No idea. Shure is the only name I've heard.
Everything's Eventual (tm)
Scarborough Fair/Canticle (Cover)