A Proof for the Existence of God Hello Dfpolis.
Good Op with some good reasoning.
The golden template of being having our lessor being coming from a greater Being is not what we observe hereabouts, for we note the ever more complex obtaining from the simpler and the simple, but there would seem to have to be something even behind the simplest—something eternal.
The template is also not impressive since it has to be discarded after only one usage, to avoid an infinite regress; however, this can be accomplished the way you have it, which is that the Being—albeit an assumption to have it be a person-like system of mind—is 'infinite'/'unlimited.
To have 'infinite'/'unlimited' to be substantial as a completed, finished state is troublesome, given that the 'infinite' cannot be capped as extant. There are dangers in using a word like 'infinite' as a stand-alone something or an amount/extent reachable, for its definition tends to some series or extent going on and on.
We also don't see that all was made instantly through an utmost power, but that the accumulations were long and slow, we barely making it through the great extinctions.
Perhaps I can add some support to what we might share as there having to be something eternal.
It would seem that the ultimate basis/existence needs be eternal, given that its supposed opposite, Nothing, cannot be. For those who might post about 'from Nothing', whatever appears from 'it' requires some capability/possibility/potential/random and so that would be the eternal something and so a total 'Nothing' was not had as claimed, bringing us back to an eternal. Perhaps the eternal is 'possibility', this needing only the same 'possibility' behind it.
It's still seems a bit troublesome for there to be an eternal something without its ever having been made, but with 'Nothing' out of the picture we have a mandatory eternal basis with no option, no choice; the eternal has to be; it must be. There is no selection or election.
What would the eternal be like? Well, how could it be anything specific/particular when there is no point before or outside it for it to be specified/designed? How does the eternal as something not at all particular be anything if it is so nebulous? Unknown, as rather formless and timeless, but, falling into assumption, might it have to be anything and everything?
Is the everything, then, all at once or little by little? We don't know the mode of time, whether it's of eternalism or presentism, so, we must profess our ignorance there, and other places, too.
What parallel do we have for something that is never anything particular? Well, the state of the universe never stops changing (precluding stillness), everything always transforming, even a trillion times a second, even if some semblances appear unchanging to our slow viewpoint. It can only be the eternal that is ever transforming (yet does so in a way that doesn't basically change it).
All in all, a 'maybe' is still a 'maybe', even if probabilistically unlikely, and so I'll give 'God' a generous 'maybe'.
Those who would preach either "God is, for sure!" or "God isn't, for sure!" are in line for being called 'misleading', and worse, 'dishonest'. Neither way can be honestly taught as truth.
That we can't know which is which, 'God' or not, appears to be the only truth to be gotten out of all this, but to some believers this would indicate that they cannot be blamed.
It all gets worse, due to fixed will, and that the supposed 'God' of the main religions can't be approved of, but those are other, secondary, stories, yet they hint that the possible making up of dogmas can run into grave contradictions.