Can you explain a little more about what you're trying to simulate and why you chose the model that you did?
Also... did you consider using known sound change processes? https://en.wikipedia.org/wiki/Sound_change
Also... did you consider using known sound change processes? https://en.wikipedia.org/wiki/Sound_change
Edit: I'm just replacing a vowel or const on a word for sound change. It may be better with natural sound change processes. I'll work on that. Thank you!