Mostly agree. Marcone and Harry know exactly what the other is, due to the soulgaze. Marcone also knows what Harry thinks of him because Harry tells him so every Tuesday. But I don't think Harry knows what Marcone thinks of him. That is why us readers don't really know what Marcone thinks of him.
But yes, their knowledge of each others helps them to use each other.
I think we were given some idea of what Marcone thinks of Harry in the earlier books. I just don't think Marcone fully understood what he was seeing, or if he did, he wasn't getting the whole picture.
I think early on he understood the kind of power Harry would wield, so he attempted to use him, cooperate somewhat with him so he could use him. Then about mid-way he realized that Harry isn't
the kind that could be used, so he tried different paths that helped him to get what he wanted from the supernatural world, the big prize for now being the coin of Namshiel.
You could be right that Harry doesn't understand what Marcone thinks of him, but Harry does understand Marcone, he is a full blown predator.