Your other solution to the conundrum of (A), that you neglect to consider, is that the universe actually has no cause.
And all of your logic says nothing about the properties of (A) that so many theists assert, particularly that of benevolence.
Had the universe itself been eternal, it may not need a cause as you suggest
And that was the prevailing assumption made by some scientists in the 19th. century who were searching for a justification to reject the notion of God, The Creator of this amazing universe
But as we now know the universe is not eternal, and that it is around 14 billion years old, that assumption is no longer a valid assumption
The universe had a starting point, and therefore, logically speaking something must have brought it into existence .........
As for the properties of (A) which can so far be deduced is that:
1-
He is Eternal (not constrained by time, as He designed the laws of this universe, including the laws which relate to time)
2-
He is Intelligent and Knowledgeable, for having designed all these laws and for having created this amazing universe
3-
He is Powerful and Mighty, for having implemented His design and brought it all into existence
His other attributes are related to why God created us and created this amazing universe .........