So it turns out that AutoHotKey can indeed play Tower Defense; I recorded a script to set up my favorite opening last night. It occurs to me that it would be quite easy to set up a simple "strategy-description language" which would be a series of commands to be executed in order. Translating that higher-level language into an AHK script would be trivial.
So at least it would be possible to track strategies and compare them. That's step one in an evolutionary approach.
Couple that with a Python front-end to make it all more convenient, and we're off to the races!