None of them. All of them.

This show (if it ever airs) should tie itself to NO previously established version of Kara in any medium. They should pick and choose which parts from ALL previous established versions of Kara across all media and from them, make a unique iteration, the best version of the character for THEIR show.

And Clark Kent is most definitely necessary. He has to be accounted for. Otherwise don't call it Supergirl, don't use Krypton and don't use that powerset. And don't expect any of his much much larger amount of casual fans to tune in.