I wasn't fond of the look of the Matrix/Twilight merger just before Many Happy Returns began; but aside from that, I wouldn't mind getting both: have the Matrix part of said merger take a more dominant role and give us an Angel of Fire that's not unlike the Linda/Matrix merger that PAD originally gave us; and have Linda return as she was last seen at the end of PAD's run.
That said, I'd also want to throw Miss Martian into this “Supergirl Squad”. She was created because Supergirl was ruled off-limits for the Teen Titans, so she's basically a Supergirl stand-in; and she has more or less the same powers that Matrix originally had before PAD got his hands on her and turned her into an Earth-born Angel.
In short, all of the above.