To me, main problem I had with Supergirl was that she originally was nothing more then a bland female counterpart to Superman. I did like Helen Slater as Supergirl though, but she gave more personality to that charecter then comics ever did.
It wasn't till saw STAS Supergirl that really started to like the charecter. She wasn't just a knock off of Superman. She came from her own planet, had her own idependant, smart-ass, yet girly personality. She also had her own style, which yes might seem tacky, but atleast doesn't look like Superman's outfit just modified into a dress. Its her own. Plus she looks so darn perky in it! lol