In my opinion, there are two types. The "good" and the "bad". The good ones simply observe us and don't interfere on a large scale, because they value development on our own and would want us to take responsibility. The bad ones, that's another story. They interfere here all the time, and I believe, the Goverment/Military and other organizations are interacting with them for technology/knowledge. In exchange, they can do whatever they want on this planet..
I'd call that Angels (good), Demons / Fallen Angels (bad). Yes, for a time, it seems that these demonic entities are allowed to do what they please -- but of course, they are being restrained by God. They must have permission by God to be allowed to do anything, or they simply are not able to. That is why it is important to not invite them into our lives or to worship them, because they will say to God: "Well look, he worships us and not you, so that means he's ours", and God will say: "very well, he's yours", but it does not please God to say that, because he's not willing that one of us should be deceived. Nevertheless, he is a jealous God, and if we worship other entities, he will wipe his hands of us (which will be fulfilled at judgement). In the Bible he has given chances to people worshipping false gods, so he does have patience, and we have to constantly sin and do the wrong thing before he wipes his hands of us, but because he is righteous, His patience isn't endless. A day is coming when God is going to send Jesus back to the Earth, and there's going to be a whole lot of trouble on that day.
It is important to have a relationship with God, because if we serve Him, and declare that Jesus is Lord, when these entities come along and say: "I need to do this or that with this person", God will say "No, he's mine". Or if God does say yes, it will be because he knows we can take it, which is a slap to the face of Satan. However, those martyrs will receive great blessings from God, once they're out of this rotten world system and in Heaven.
Of course, many will claim that entities and aliens have done nothing but good for them. But this is a trick by those "bad ones" (ie: demons). Of course they want to appear as an angel of light, like a wolf in sheep's clothing, to have us deceived. They're not going to show up with horns, a red cape and a pitchfork, declaring that they serve the lord of darkness and their ultimate aim is to take your soul, are they? That is why so many people in the New Age movement are duped. They sincerely believe that what they're channeling is good and wants to help them. These entities tell them that they are gods or can be gods and that they can "ascend" and be masters and that there is no God, etc. It is a deception. A day will come when these New Age types will stand before Jesus, and Satan is going to be there accusing them saying: "They did not serve you, they served me, so he's mine". Jesus (who is the Judge) will say: "very well, he's yours". THAT is the plan behind the whole alien deception. It's a battle for souls, not to "enlighten humanity, get free energy, and have us traverse the galaxies". That's a lie! And a very shallow one in the big scheme of things.