Hi, nice stuff.
Is it possible to build in a comparison based on trigrams?
Start at pos 1 of the string take 3 characters and hold them, shift 1 position and do the same, until the end.
Do the same for the second string.
See how many trig's are the same among the strings and calculate the percentage to the total number of trig's of string 1.
In this way you get a good idea about the similarity between the different writings of street names, etc.
Keep up the good work