Flatline is squishy and after Mandrakes rezz you can two shoot the revived opponents. As if for Mandrakes skill you can use mark to block it. And even if it kicks in you can still see and hit your opponent. Only the Ai is confused by it.
Well those skills should be implemented so that they are not the default heroes. But they should make it risky to run Flatline, Ifrit, Mandrake, Nightghale, and Panzer or Dogface. Now this team is to safe to run with not enough counters outside roughly the same.