Algorithm using soundex() or metaphone() to create Mad Gab style phrases

I'm attempting to create an algorithm that will suggest Mad Gab style phrases.

The input is a set of phrases. I also have a set of keywords that I'd like to use when possible. Currently, my solution is simply brute force:

• loop over phrases (character by character)
  • if keyword is found
    • store keyword and branch (recursion)
  • increment character count

However, the problems I am running into are:

• Account for compound keywords, e.g. "catches" can be "catches", "cat" + "cheeses"
• Allow literal terms - "the", "and", "one", "two", "three".
• How to suggest terms that are not keywords. i.e. fall back on something like the system dictionary when keywords or literals can not be found.
• Skip phrase segments. Right now it just does one pass through. But consider the case where the phrase starts with something unmatched but a few characters later contains matches.

I am most familiar with PHP and MySQL. However, I am open to another technology if it provides a better solution.

I am also interested in any additional suggestions. Particularly ways to use the second parameter of metaphone() to make harder suggestions.