It is interesting to read the Sikh concept of God. There is much that to learn from here. I can see, reading the wisdom of the Sikh gurus, why Joseph Smith said that Heavenly Father has inspired many good people throughout the ages to bring greater enlightenment to their nation, and that the teachings of many were given to them not to lead people astray, but rather to bring them closer to the truth.
For example, I appreciate how content the Sikhs are to meditate on God, to contemplate his goodness, his faithfulness, his perfection. In my own church, I think we often get into the trap of focusing on our human frailties, which will never exalt the human condition. The gurus got it right, I think, when they suggested that it is by looking to God that we become one with Him, not by focusing on our weaknesses, shortcomings, sins, etc.
As best as I can understand, Sikhs see him as genderless (they use "he" for convenience in translations), formless, and incapable of incarnation (so, no Trinitarian idea about God being able to come down to earth and become flesh, at least). But they would probably also have a hard time with the concept of the Godhead--three gods (Father, Son, and Holy Ghost) working in unison. Sikhs are very adamant about their monotheism. When the first guru introduced the concept in a land dominated mostly by polytheism, it was a step forward. He also taught equality (of the sexes, and against the concept of caste).
I am surprised to find that Sikhs believe that God has created many worlds, and many inhabitants thereon. For example, "There are worlds upon worlds of His Creation. As He commands, so they exist. He watches over all, and contemplating the creation, He rejoices."