I like your function. But I'd call it differently...

People who don't memorise passwords would think that punctuation marks would make a password harder to remember, but they don't. kmJPJ-wLKA is no worse to remember than QDBLhUCcjH, and provided the punctuation is included at random (rather than forced to be there), security is enhanced.

Now, the other poster's alternating-consonant-vowel passwords are even easier, but those are less secure. There are ways to fix that up a little, though, if you're willing to sacrifice uniform length, without a horrible impact on ease of remembering... I'll post that separately, though.

 --jonadab