[saganus]

It might be interesting to use the word frequency of the target language as some sort of weight for each word, or maybe as a multiplier for the number of times that word will get pushed to the back of the queue, i.e. the words with the most frequency get to be repeated more than 1 time when pushed to the back, or something like that.

[lyle_nel]

I see what you are saying. To some extent this is already true ,since high frequency ngrams(substrings) already dominate the gene-pool if they happen to facilitate the production of a large amount viable offspring. That is why you would see swearwords with high frequency since that is what many people use for passwords(in the case of the myspace list).