Yeah but there a difference, The odin power is more than just a tool to be used in battle. At first Thor used it as if it were just an extra power. By the time he regained it during Ragnarok, he blinded himself and gained the wisdom like his father through death. At this point he was able to stop mangog with a whisper. His knowledge of the powers was really limited. Sort of like how John Stewart has one of the most powerful weapons yet he uses it for base attacks.
didnt he kill hulk and thng with one hand, w/o experience. now im not saying din couldnt do it, but that is one hell of a powerup. and thor used it like he did when he was classic, and classic thor fought people way stronger than him, mangog,ss,thanos,galactus celestials etc, anyway thor has all kind of experience in this feild, so y cant he beat thanos.
Thor murdered them because he was classic thor but he did not have the limitations on his powers like he usually does.
As far as beating Thanos, Thanos is a very weird villian, he has both a combination of intelligence, strength, as well as other capabilities. He basically what happens when you take Doctor Doom and give him a shit load of cosmic powers.
I say it depends on Thor. If this is when he first gained the odin force than I say Odin. Odin had a grasp of the powers better than thor and he could summon a greater variety of powers. If this is Thor after learning the rune spell, then Thor since he had achieved levels even greater than his father.