Absolutely think you should react to killing voice next- it’s 100% live so it really showcases their vocals and it’s basically snippets of a bunch of their title tracks since debut so you get a taste of how varied their discography is.
As for MVs my personal recommendations are:
Home, Getting Closer, Fear, Home;Run, and Falling Flower (which is a Japanese release)
But honestly you can’t go wrong with anything seventeen IMO