Does the Bible give us any indication of why God created such a vast universe with so much stuff in it?

The popular view of Mormonism is that when you die, you get your own planet. Here is a more precise statement of the view from the Wikipedia article on Mormon Cosmology:

Mormon cosmology teaches that the Earth is not unique, but just one of many inhabited planets,[25] each planet created for the purpose of bringing about the immortality and "eternal life" (i.e., the highest degree of salvation) of humanity.[26]

There are millions of Mormons and billions of Christians. At the time Mormonism was founded, it was not clear how many planets there were outside the solar system-- many planets were undiscovered. It might have been a stretch in the early years of Mormonism to claim there were enough planets for every possible believer.

Even if we limit our view to Nicene Christianity, it is clear that there was a command to multiply:

God blessed them and said to them, "Be fruitful and increase in number; fill the earth and subdue it. Rule over the fish in the sea and the birds in the sky and over every living creature that moves on the ground." Gen 1:28

Many have held that physical death (i.e., a limited lifetime) was not in the original plan for God's creation. A command to multiply and no death logically leads to geometric progression of population. If there's only one planet, it probably would fill up soon.

But the universe is immense. My favorite measure of the immenseness of the universe is that one previously-thought dark region of sky, when examined by The Hubble Telescope, was shown to contain 10,000 galaxies.

Thus, a plausible reason for the immense universe is to provide homes for an unfallen, geometrically increasing population of humans. It provides an apologetic argument for God's providence that would not be there if say, the observable universe had consisted of merely the island of Bermuda.

While it's clearly implausible for humans, in their current fallen state, to travel to far galaxies without any Divine intervention, "all things are possible with God."

Look at it from a historic point of view. We roamed the earth looking for the end of this planet (thinking it was flat and there was an ending, but what kind of ending was our question). Now, we roam the universe (thinking that there is an ending, but what kind?) Did one of the Star Trek movies ever reach the end of the universe? If so, where do we go from there? Do we just start drawing detailed maps of the universe as we started to do once mankind realized that the earth was round?

Does the Bible give us any indication of why God created such a vast universe with so much stuff in it?

No.

1. Scripture primarily focuses on three things: The nature of God, God's actions on Earth, and how humans should act on Earth.
2. The Bible was written during a time when most humans (lower than kings) were just struggling to live day-to-day. They needed hope and a reason to live. Relative to other generations, a much larger percentage of the human populace was trying to satisfy lower levels of Maslow's Hierachy of Needs.
3. The Bible was written before the printing press, before mass literacy, and before the Enlightenment. Emphasis: Books weren't plentiful, most people couldn't read, and even if they could - Astronomy wasn't sufficiently advanced to facilitate a widespread appreciation for the vastness of the universe.

Yes, the Bible specifically addresses this question in Psalm 136:5

"(Give thanks) to Him Who by understanding made the heavens, for his steadfast love endures forever;"

Now, for you to understand why the good of living creatures on earth (just on earth, with no need for any other inhabited planets) requires an enormous universe, you need to know two pieces of data, one from astrophysics and one from relativistic cosmology.

From astrophysics: it is well known that both ultra-high-energy (> 10^18 eV) cosmic rays and gamma ray bursts have extra-galactic origin. Therefore, a higher large-scale matter density in the universe, since it would imply greater closeness between galaxies, would imply a higher incidence on earth of these highly dangerous particles (cosmic "rays" are actually protons) and radiations.

From relativistic cosmology: to keep the large-scale matter density in the universe no higher than it actually is, you need a minimum size of the universe which is indeed enormous. For anyone interested, this can be understood with just engineering-level math, taking the Friedmann equation as a starting point.

In brief, an enormous universe is necessary just to keep the level of extragalactic radiation reaching earth low enough for our good. God knew that and took care of that, because, as the Psalm says, "by understanding made the heavens, for his steadfast love endures forever".

Short Answer: Yes, the Bible does give us some indication as to why He created the rest of the heavenly bodies.

1) Scripture describes Day 4 of the Creation week as follows:

Then God said, “Let there be lights in the expanse of the heavens to separate the day from the night, and let them be for signs and for seasons and for days and years; and let them be for lights in the expanse of the heavens to give light on the earth”; and it was so. God made the two great lights, the greater light to govern the day, and the lesser light to govern the night; He made the stars also. God placed them in the expanse of the heavens to give light on the earth, and to govern the day and the night, and to separate the light from the darkness; and God saw that it was good. There was evening and there was morning, a fourth day. -Genesis 1:14-19

Here we see God's purposes behind the creation of the "lights" in the heavens (the Sun, Moon, and stars.) Collectively they serve the following functions according to Genesis 1:

• They are useful to God for giving signs to mankind

• They are useful for marking (and causing) seasons

• They are useful for marking (and causing) days and years

• They provide light to the earth

• They "govern" the day and the night

• They are useful for separating (or distinguishing) light from darkness

2) In the book of Psalms we have a couple psalms of David which give us some additional insight:

The heavens are telling of the glory of God; And their expanse is declaring the work of His hands. -Psalm 19:1

O Lord, our Lord, How majestic is Your name in all the earth, Who have displayed Your splendor above the heavens! . . . When I consider Your heavens, the work of Your fingers, The moon and the stars, which You have ordained; What is man that You take thought of him, And the son of man that You care for him? -Psalm 8:1-4

Here we see that God's works in the heavens (the stars, etc.) serve the following functions:

• They proclaim God's glory

• They inspire awe in men about the greatness of God

• They serve to humble man before God

3) The vastness of God's creation in the cosmos served at numerous points in Scripture as a reference for man to understand something innumerable. For example:

And [God] took [Abraham] outside and said, “Now look toward the heavens, and count the stars, if you are able to count them.” And He said to him, “So shall your descendants be.” -Genesis 15:5

The list goes on, but these are probably the clearest passages in Scripture on the topic.