How can a creationist invoke a created universe and assert its logical consistency, given that almost nothing (as measured by volume or mass [1]) inside the universe was created by intelligence? It's only a tiny fraction of things in the human world, the rest is created by intelligence-free, unconscious mechanisms. Even the only known intelligence inside animal brains is created by intelligence-free mechanisms. See neuroscience for details on how.
Note that this applies to the universe at every stage in human history. It applies to all parts of the universe that were previously unknown, or "outside" the universe as it was defined in a previous time.
At no stage in history has the universe outside the minds of humans been verified to be created by conscious intelligence. Be it the Nile Valley, the European continent, the earth, the solar system, or the Milky Way galaxy.
How is creationism logically valid if every time humans have expanded the visible "universe" we have access to, it turns out that the same or similar intelligence-free fundamental laws and processes are what's doing the creating?
Doesn't creationism commit a special pleading fallacy by asserting the entire universe MUST be different from what occurs inside it AND ignores the history of how each time the universe has expanded, the old parts were found to be created by intelligence-free mechanisms?
Doesn't creationism commit a 2nd special pleading fallacy by asserting the entire universe works the same as the infinitesimal fraction of the universe that humans are responsible for?
Science proves simple parts with simple rules can combine into very complex systems (i.e. intelligence simply isn't needed to create complex, magnificent results) so the creationist argument from complexity/amazement isn't logical or consistent with empirical observation, whereas atheism is logically consistent with all known evidence, and all definitions (i.e. sizes) of the universe.
"Theists will define their god and attribute qualities to their god such as intelligence, intentionality and inspiration."
The only known cause of these attributes is intelligence-free processes, mechanisms and laws inside the universe. See neuroscience for details.
It is not logical to violate the parsimony principle, i.e. assume there is some other mode of existence or way to have these qualities.
Every new assumption without empirical evidence doubles the chance the conclusion is wrong. Theism adds hundreds, thousands, perhaps millions of philosophical assumptions, making it both logically invalid and probabilistically impossible.
"What would be a logical explanation for an uncreated universe/multiverse?"
As emotionally unsatisfactory as it is (because it says the "creator" is not, in any way like us), the logical explanation for an "uncreated" universe created by intelligence-free mechanisms is what science continually tells us: that astounding, complex structures can be created with only simple intelligence-free rules and without intention, from simple parts interacting in 4D space-time, 2 more dimensions that is required for the leap from simple dynamical systems to complex chaotic systems.
[1] Let's assume everything inside the livable part of earth was created by humans. Divide that thin spherical shell volume by the total volume of universe. Rough guess, it's about 10^(-100), yet this minuscule fraction is what creationism demands is somehow inverted for the case of the universe itself, based simply on the way humans work and subjective, unreliable human emotion of amazement (mostly due to ignorance). Creationism really is an inversion of logic and all known evidence.