1. Did Silly Sunshine have wavy hair when she was fresh out the box?
Yes, I ll second that
It was a gentle wave but certainly she was intended to have a nice wave to her hair.
2. Is light pink core 7 hair more likely to get frizzy than other hair?
Yes, towards the end of G3 the line started to use clearly different quality hair on any release that was exclusive and continued that trend into some of the core 7 line. Its not specifically that colour however thats prone to issues - it seems anything on the pink/purple/blue (which is just about everything) range.