I personally would not have made that trade. You gave up a 1000g female single gene, and a 400 gram female double gene for a different 1000g single gene female that is nothing new or 'up and coming'.
Fire has been around for a long time now, and you probably could have purchased a decent size fire for much less than the value of the two snakes you traded for it (given their sizes).
That is just my opinion.