Source: marvelcinematicuniverse.wikia.com

3. Where are all of the other aliens?

So the Chitauri found Earth, and were met with one heck of a resistance. And the Ravagers visited the sprawling world in the 80s to pick up a young Peter Quill. Before that, Ego the Celestial visited for his own purposes. And the Asgardians have been planetside for hundreds of years. But why no one else?

Like, there are other aliens out there. Guardians and the upcoming Thor Ragnarok have shown us tons of them! So why are they staying away from Earth?

And don't give me that Oh, Earth's so unimportant and backward that they leave it alone BS. Earth has numerous superhumans, the Sorcerer Supreme, full contact with the Asgardians, multiple Infinity Stones, contact with the Inhumans royal line, and did I mention MULTIPLE INFINITY STONES!!!!

Earth should be swarming with alien life forms, but no, apparently they have their own sh*t going on. Good to know that no one cares about the most powerful things in the universe. Nothing of note there.