There is another interesting point emphasized by the Ramchal in דעת תבונות. He says that Hashem’s ultimate greatness is unfathomable by man. The more one gets a glimpse of G-d, the more he realizes that his real knowledge of Him is like a drop in the sea. This should cause the seeker to become exceedingly humble.
The real pursuit in man’s quest to know G-d, should be to focus on His Oneness. He should reinforce to himself that Hashem’s uniqueness is far different than anything that exists in the universe. Such study is productive and bears fruit.
The Talmud in מסכת חגיגה alludes to this idea by cautioning people not to delve into מעשה בראשית, the act of creation. We are also warned not to try to understand מעשה מרכבה, the incident of the chariot in the Book of Yechezkel. Such studies need special care and guidelines.
However, delving into how Hashem is unique and One, does not require such preparation and care. It is more of a direct means towards getting closer to our Creator.