It is incomplete to consider agnosticism as 'I don't know if there's a God'. Many agnostics more specifically believe that the existence of God is unknowable by nature.

"Agnostics claim either that it is not possible to have absolute or certain knowledge of God or gods; or, alternatively, that while individual certainty may be possible, they personally have no knowledge"
Agnosticism - Wikipedia, the free encyclopedia

I believe in "God" but I don't view God in the religious sense. Mine is more of an Eastern understanding of God as the intelligence and being that pervades everything - we are all a part of it. It is sublime. Humans can develop a personal relationship with it. The more aware you become of the super-being, the more you experience it. That is why hope and belief play a large role.

In my view, most people are too closed-minded to suspend their disbelief. As such, they experience what they believe - nothing more, nothing less. Usually this is what their culture has taught them to believe at a young age. You will always experience the reflection of your true beliefs. God will appear as what you believe God to be.

That's why no one can agree on it.

God, the super-being, is. All people have this knowledge within them, as well as a desire to grow in their awareness of it (which is ultimately an awareness of their larger self and life). Eventually this asserts itself. It is inevitable. Just a matter of what path you take to it, in this lifetime or another.