I have two iTerm profiles setup, a dark one to use the Pastel theme and a light one to use solarized light theme. Is there any way to have Vim change the background and colorscheme options based on what profile iTerm is currently using?
You could add a login command to either profile (in iTerm2 there's a "send text at start" option, I don't know about regular iTem) to alias VIM to use the color scheme you want:
alias vim='vim -c "colorscheme pastel"'