With the new Vortex cards you can get a pretty supportive half deck for about 9-10 stars.
Any Level 3 or 4, with your best options being Deea, Sunder, or Dagg.
This leaves you with 15-16 to work with. If you pair it up with Piranas you could run something like this:
Just a thought...
That's one way to do play. Only "bad" card in that half is Neloe and she's isn't the worst card ever. But I'd rather the inverse, make the Vortex the 14 to 15 half. Oflgn, Dagg, 3*/4* of choice and a 2* of choice is also a nice half. Especially since Oflgn wins games by himself.
My main thing about a low starred half for Vortex is that you'd rarely maximise the bonus. With a big half, your offense could have it's edge for plenty of turns. And if the opponent ever feels like stopping you, you go at them again! That's just me though...