His interest in the Thor movies was in overthrowing Odin and ruling Asgard, so he did crave power. Doing it by open force rather than trickery wasn't his usual method, no, but it was the opportunity that Thanos and the Other offered him after saving his life, so he went along with it since it would give him what he wanted. The end was still the same, even if the means differed due to his circumstances and alliances.
Actually, in the first movie he said "I never wanted the Throne! I only wanted to be your equal!"
It was more him just wanting to be treated with equal respect to Thor, and that envy and resentment led to his "Let the Frost Giants screw up his coronation" prank and THAT caused things to spiral out of control and by accident landed him the Throne.
He didn't care too much about the Throne of Asgard until Dark World, and that was more out of spite to his family than purely for power.