The first column is a little less formal and more common (in my understanding of typical American English at least), so I'd give it a more prominent color. You can mark this scale with something like an upside-down triangle to show a simple transition from a lot at the top to none at the bottom.
|totally _____||extremely _____|
|really _____||very _____|
|pretty _____||fairly _____|
|kind of _____||somewhat _____|
|not so _____||not very _____|
|not _____ at all|