Maybe you will get some answers with the second season
or perhaps you will have more questions at the end and you will be completely lost. XD

I don't dislike the idea of a second season but I don't think it's needed.

She wasn't really "Godlike" for a God. ^^
I mean a God should at least know that he/she is a God.
And if you think a bit about this concept I don't think the Creation would work like that.

I think it was really just a slice of life type anime. The fact that she was a god was an extra thing to add some excitement to the story line.
The conclusion of the story was simply that she decided to stay with them and live that life instead of destroying it and making another.

Now if any of you guys have played American Mcgee's Alice, you might end up with a different look of this anime. In Mcgee's game, Alice was a little girl who ended up in a coma after her house caught fire. Now, even though they tried to push Haruhi as being a god, I still have the thoughts that maybe it could be something along the lines of Alice's coma. After all, we can have some control over our thoughts so the idea of having her friends actually turn out to be aliens or espers isn't unreasonable if she was living inside her own head.
Of course that would be way too sad an idea for a story line. It made for a great game though.