The Animated Guide to Emacs Paredit 12 years ago
It's called rainbow delimiters and I use it with everything.
http://www.emacswiki.org/RainbowDelimiters
As for the unbalanced delimiters, I just M-x paredit-mode, turn it off, make my fixes (which is easy because rainbow delimiters shows me exactly which delimiter is out of place), and then turn it back on again.