We pick and choose the bits of Sikhi that speak to us, and then we spend a lifetime trying to justify why we broke the rules. No wonder nobody takes religion seriously when it's rife with hypocrisy.
wjkk wjkf ji
you asked very good questions!
to conclude, I can say only one thing,
"its not an important that there is a God or not or his existence, important is "believe in something" and you can name it anything if you don't agree with the word 'God'.