This is fun, thanks for doing this.  I did the same thing for Dreamblade, a similar game, when it came out--well, pretty close, regression analysis of creature cost.  A few things I learned:
1) trying to cost abilities is really hard, as you basically have one or just a few data points for each.  I ultimately did what one of the respondents recommended, and just tried to figure out the value of the stats, effectively pricing the abilities.  Less neat, but useful--you can decide if a given ability is worth it's cost.
2) several sets in I had enough vanilla (special ability free) guys to run a good regression on just them, which basically cracked the code, but I got decent results from the first set just running the regression ignoring abilities, so you might try that.  The results were biased, of course, as some good abilities are correlated with certain abilities, but it still gave some useful info.  At least I would like to see the results!
3) after a few more releases you may have better luck pricing some of the abilities, if multiple creatures get them.


Keep up the good work, and thanks again.

Yes,no, no (sold out), no

Great demo, Well done.