Lyrics have always been my weak point.  I'd go 20 years with one verse and nothing else.  I will say that the more you do, the better you get and more free with your ideas.  I don't use too many rules because I don't know them but it could why I'm here instead of in Hollywood or Nashville.  :-)  You've got a really good start here and a lot of good advice.  Don't be afraid to pick someone and ask them to co-write with you.  I just did that with Herb.  It would have been another 20 year song but it isn't now!  Good luck Janet, you're a great musician.