I would be interested to know if anyone finds my program useful. Latin, German, French, etc. are surely too large and inclusive. Zipf used a chrestomathy from many different periods for French, surely a bad notion as a first step.
Letter counts vs. phoneme counts.
Letters are graphemes at best, not phonemes. What do we do with editions, and which do we choose. For example, it is common to distinguish between i and j, u and v in editions, though these are Renaissance inventions for the most part. Whatever is done, it needs to be spelled out carefully, if it is important. Where an edition includes two or more witnesses, we need to be careful to distinguish between them, perhaps not so much in the matter of letter counts, but otherwise.