To address the topic in the thread title, which theory is simpler?
The universe popped into existence pretty much in the configuration as we see it now 6000 odd years ago.
As the observable universe is expanding, it should have been denser and hotter in the past.
Neither, simply because both popped into existance at one point in time, and who says that the creation model CANNOT be expanding, moving around in circles, jumping up and down, or just plain existing. Same with the universe expanding, amazing, it was created, and it's expanding, that is simply amazing, well not really but anyways.
Atheist say the universe or matter just exist.
Creationist say that God just exist.
The only difference is that God has the ability to actually perform the creating process while matter, which just exist, would absolutely most positvely 100% without a doubt NOT start expanding for absolutely 100% without a doubt for no REASON. And using the atheist model, matter wouldn't do anything, because it simply 100% without a doubt does not have that creating ability on its own. Offcourse atheist would deny that matter would actually need a reason, or guiding abilities because in the atheistic view EVERYTHING just randomly POOFS into existance with zero guidance, and zero intelligence.
It simply amazes me that Atheist actually believe that planets, stars, and gravity just simply expanded into existance with absolutely zero guidance from ANYTHING. Remember that matter on its own has zero guiding ability.
From a logical point of view, God creating the universe just makes a whole lot more sense than nothing creating the universe, and all living things.
This is also another example of the Atheist model of the origin of matter, and the universe: Matter just starts to move and bring all these elements perfectly together to create planets, and whole galaxies. It just happens as the atheist like to say. Well using that train of thought, a box legos should randomly start to expand and start to create an entire Universe over a series of billions of years. Remember again, all of this with absolutely zero guidance. Also, remember that Atheist do not like to answer where matter came from, it just exist.
Another example of the Creationist model: God creates the universe, and how
He did it is a mystery, and also there is some slight evidence that it is expanding and moving, but whole solar systems are moving to, also gravity seems to be working just fine. God has created a working/moving Universe. Amazing, but amazing to the atheist view is Matter has defied the odds of actually doing something, and created a working/ moving Universe. Also, remember that Creationist do not like to answer where God came from, He just exist, oh yes He does.
Remember, if the path you have taken has lead you to either of these views, then consider this.... What is the rule?