This has been my "go-to" definition for a while, though I'd add a caveat: complexity can be subjective, based on the reader's particular experience or background.
Whenever I use FRP, I'm worried that the code is super maintainable and readable for me, but a hell for a less experienced coder.
Yes, else it ends up as some form of Perl Golf
Yes that's better. The intent was to not have unnecessary code (often happens when when 'cargo-culting' some design pattern).