A. Imagining things coming into existence without a cause
B. Imagining a first cause existing beyond our cause and effect (space/time) universe
It is actually more plausible to consider that the universe in some state, always existed. The expansion of space does not necessarily point to an origin of the existence of the universe. It only proves that the universe in its current state is expanding. It is possible that the singularity from which the universe expanded is eternal. Maybe the universe oscillates between expanding and contracting back to its singularity only to expand again.
It is far more plausible that the eternal source of the universe is a very natural and very simple entity than the complex, super-intelligent being that you are putting forward. So saying that there must be an eternally pre-existing first cause does not naturally and logically lead to the idea that that first cause is a complex, super-intelligent person. A very simple non-intelligent, non-conscious, inanimate entity is far more plausible. Have you heard of Occam's Razor?