It's an impossible question. I don't 'believe' in any form of God. I think we are the highest thinking lifeforms, and therefore we can do the most 'interesting stuff'; crocodiles have been around a long time and are awesome (from a human POV such as mine), but really 'is it worth it'? I mean, they are born, they live, they die. Great.
What is the *point* of life when you can't think higher thoughts and do higher things? Does it matter, either way - there are so many stars, planets out there - are we all quarks in some larger being, or do we host universes in our own bodies?
If we didn't exist there'd be more alpha predators, more climax forests. There would BE beauty as we define it; but with nobody to define it....
IOW: Fuck knows.
How can you be sure that humans are the only species, flora or fauna, that can have higher thoughts and do higher things?
If you could tune into alpha waves how do you not know that you could communicate and learn amazing things from plants? Why is our thought and communication the only possibility? We already know that trees communicate through fungal networks in the soil. That is some "interesting stuff", can your higher thinking self do that?
Sometimes I like to think that maybe dolphins are the most intelligent species on the planet. They live in a land of abundance and spend most of their time playing. That is what life is about, play. We take it much to seriously. They may be looking to us and thinking that we are entirely stupid, "why if they were more intelligent wouldn't they get what it's all about?"
Having higher thoughts does not give life a point either. Having higher thoughts can get us stuck in a moment that doesn't even exist. We can get lost regretting the past or anticipating the future without even appreciating the now. Being lost in contemplation while missing what is a-happening now seems kind of pointless too.
To answer your question, I think that we do hold the entire universe within our bodies. We are it, everything, and nothing is separate from us, just as the flower is not separate from the field, its stalk, leaves, or roots.
Would the earth be better without us? Who knows. I agree with other posters that say you cannot define what better is anyway. I think that if deep down we thought we were important we wouldn't have developed the atomic bomb and other means of entirely wiping ourselves out of existence.
Earth is only special because humans are on it.
That seems like a very narrow view.