My friends and I have a large collection of ships. We've played almost every match up. I've seen Decimators/Flying Saucers win, and I've also seen them die in the first two rounds. I've seen random builds like 2x A-Wings + 1 E-Wing that wrecked everyone. The same thing with 2 HWKs plus another ship. But the current tourney results is what happens in head to head games, there are tiers. You can relate this to Street Fighter, League of Legends, etc. Some ships/characters will just be better, almost uncounterable. That's your top tier. Some ships will have multiple hard counters, that's your middle tier. And some ships are just niche/can be beat by most, that's the bottom tier/we don't know what to do with this yet tier.
Hopefully....Wave 7 brings about something that gives us at least another hard counter to turrets/swarms. Maybe it will be bombs, maybe it will be another awesome upgrade card like Rebel Captive.