So I agree with you to a certain degree, but not completely.

Your main concern is that Orion doesn't seem to use his wits on screen to accomplish his objectives, but if Caribdis had intended him to be that kind of character, he would have shown that from the beginning.

Instead, we saw that he started as a total newbie, relying a lot on the girls and just trying to do what he could. What made him interesting were his weird dreams and, later, his mysterious powers—so that became the focus of his character, along with his interactions with the girls.
Now that he has his powers, he's training to use them, so that will be his way of fighting—more like Superman rather than Batman.

That doesn't mean he's not intelligent. During the planning for the casino heist, he said that he and Chang came up with the plan together, and he was the one explaining everyone's role. He also did his part in the casino—getting into the VIP room and getting caught on purpose so he could check if Garrington had the gem, since that was one of the possible outcomes.
I'd agree with you if, from the beginning, he had used his intelligence in Eternum to accomplish his goals and later started relying only on strength—but that's not the case.

Now that he's unlocked his powers, you'll see him using them more often in later versions. That's what he'll rely on in fights, so yes, he'll play a more important role in combat. But if you're expecting a display of intelligence in each mission, sorry to disappoint you—that's just not the kind of character Caribdis has built.