non-deistic solutions to creation

let's look at some non-deistic ideas for the creation of the universe.

1. the universe has always existed; it extends infinitely back in time and infinitely forward into the future -- in some form or another, and not necessarily in its current form. Seems to be contradicted by the big bang theory. although, the big bang might have started within some field or construct that existed forever. But then where did that come from?

2. big bang theory sets time to start at zero and proceed forward. there is no "before" the big bang. But, is that some sort of "self-creation" or spontaneous creation or ex nihilo (creation from nothing)? And why don't we continue to observe spontaneous creation, if that's a property of reality? Again, is the context a "larger" context or field where this takes place. and where did that come from?

3. I will accept a non-deistic theory of creation if it's in the language of science. But is this possible? How do physical laws account for creation of the universe? Where do physical laws come from? It seems to be a russian doll situation -- our doll is inside another doll, et cetera -- but that never ends.

4. The benefit of a deistic theory is that it doesn't need to follow the constraints or logic of science -- and so the explanation stops there. It flows from the idea that a scientifically describable universe cannot create itself ex nihilo, and has to exist within a context of a non-scientific construct, like a deity.

5. but is that just an "easy out" solution? a clever trick?

6. is a physical universe with infinite duration a reasonable scientific idea? But how to reconile it with the big bang theory? And even if it could be reconciled -- is that acceptable? to just posit space-time as the ultimate background that was never created, that always existed?

7. Am I hesitant because I have trouble contemplating infinity? I understand it mathematically, from a layman's point of view -- real numbers and so forth. Heck, even pi is infinite. Accept that, so why not an infinite universe?