Thanos is absolutely no match for Tyrant. It hasn't been mentioned yet, but simply to steal the orb, Thanos needed to create a diversion by using Jack of Hearts, Ganymede, Terrax and Legacy. It's all about strategy, which is why most say with prep time Thanos can beat anyone. He created a diversion, took the orb, survived Tyrant's onslaught (which was far from 100%) and escpaed with his life. That was Thanos' plan and he considered it a victory, as do I.
Could Thanos face Tyrant alone. Absolutely not, he would get stomped. But I don't consider the battle as Thanos owning Tyrant.
As for the battle with Wonder Woman, I see it like this. Thanos with preparation wins for sure. From what I understand, Wonder Woman is less than Superman. Silver Surfer (unfortunately which I think was always a plot device because the Surfer never uses his power to it's full extent) is less than Thanos. Silver Surfer is at minimum an even match for Superman. By my logic, Thanos should win the fight. But, like I said, I don;t really know enough DC to make a claim.
@Lance Uppercut: I'm just saying that is an assumption. It was never stated that the orb's power could be used, although it is possible Thanos was using it. All I am saying is that Thanos wanted a challenge. That challenge was stealing one of Tyrant's orbs. Thanos considered it a victory, because with or without the power of that orb, he was able to face Tyrant and steal it from him. I am not siding with Thanos, because I don't know enough about WW to pick a side.