I think that Hunt, Dumba, Brodin, Spurgeon, and Suter(with the right linemates) are good choices in 3 v3. Koivu should not be out there, and maybe not Parise. Zucker has the speed, but has been guilty of a lot of costly errors in the past in 3v3. Fiala is an unknown...apparently we are crowning him after he finally strung a few decent games together. Before that, he was dogshit. Let's not pretend otherwise.
Kunin is barely fast, smart, and skilled enough. Greenway...not so sure. Staal(barely) and Zuccarello, if paired with speed. I don't mind the choice of Ek, if he is paired with players that have puckhandling and offensive skill. Fiala, if paired with defensive skills.
Bottom line is that we don't have the horses to be effective at 3v3, AND that Dubnyk can't seem to stop a beachball, nor handle the puck, which gets much more important in OT.