Is it ok to not believe in any god/gods or should one keep trying harder?

To believe, or not believe something doesn't fall into the category of "wrong or right" that I can see.  People believe something because they have evidence or the argument seems logical, or they don't believe because of contrary evidence or argument.

Try harder, meaning better brainwashing?

Of course it's fine.  Why would anyone want to believe in any gods?

It is ok to realize that gods are human ideas and can be traced back to the cultures that invented them.

Then give it back to Breakthrough and ask your own.

How much actual choice does one have over that?

Drawn to, not drawn to?

Can't see trying working.

Write your own goddamn questions.

I'm not sure what you mean by asking if it's 'ok'. Ok with whom? Ok in what way? If you don't believe in any gods, then you don't. Simple as that. I don't know who it has to be ok with. 

It's perfectly okay to not believe in god since he doesn't exist.

You can only believe what you know to be true. You cannot believe what you do not believe.