Deep question, Brett.
I don't believe planets are of any particular value to the universe. They're what happens when a heavy-element laden star explodes and its remnants mingle with others' and coagulate into a solar system--inert, inconsequential mass, neither producing nor absorbing much energy.
Life on earth, OTOH, consumes much more of my limited philosophical musing. The best thing to happen to life on this planet--that is, the one thing that enables life to continue--is evolution by natural selection. It produced multi-cell organisms, which are much more robust and flexible than single-cell. It favored sexual reproduction, which enables evolution to proceed quickly when it needs to, but also to maintain stable forms. And, it causes life to propagate in unimaginable varieties. Whatever niche exists, given enough time, evolution will find a way to fill it with living creatures.
I believe that because of evolution, some species will come to dominate. That's the way genes work. Random mutation tested against the environment will produce species that compete against each other for dominance. And those with a better "solution" to the existence problem will increase in number at the expense of those less well suited.
We are, so far, one of the dominant species on this planet. But what will happen in the next Ice Age? Global warming hysteria notwithstanding, the planet IS going to freeze again, just like it did 100,000 years ago for nearly 80,000 years. WTF do we do then? Continents will be mostly uninhabitable under a mile of glacier, then when the thaw comes, the surface will be scraped clean, ready for rehabitation by whatever species adapts most successfully. Will it be us? Apes? Gigantic cockroaches? The Borg?