This Supergirl had Helen Slater's naivety at first, but slowly developed a personality that was sweet...but she knew she could punch you through a wall if she had to.
They played around a LOT with her story, as they did with every storyline on Smallville. But they did work in a few things from the comics like her going to to the 31st century to join the Legion and using glasses and a wig to hide her secret identity. In some of the odder things they did, she could fly and Clark couldn't and she even kind of "became" Supergirl at one point before Clark became Superman.
It was messed up yeah, but it was Smallville. They really didn’t try to reign into the DC mythos until the last couple of seasons.
And it's no secret that I would have loved to see Laura Vandervoort get her own "Supergirl" spin-off show. But that didn’t happen.
