im writing a rock ballad and just wondering what is common in these like what form are the verses in and should there be a lot of different parts to it stuff like that its slow tempo and mainly arpeggios with another guitar playing chords its kinda like dont cry by guns n roses im new to writing songs so if anyone can help me then thanks
some ballads like nights in white satin or november rain have unconventional forms with long bridge and instrumental sections.

If you're into GnR ballads, listen to some Elton John. I believe Axl held him in high regard, and some of his songs(written by Bernie Taupin) are great examples of ballads.
rock ballards can be pretty free form, and often have long bridges and instrumental sections.

a simple way to do verses is to have few instruments, quite quietly and undistorted playing arpeggiated chords, maybe just an acoustic or piano. then when it comes to the chorus kick in a distorted guitar, double or triple tracked (les paul/marshall style tone) Playing some power chords that are held for a bar or half a bar each.
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