Does anyone have any theories or hypothesis about "aliens" being human time travelers from the future?

I've read a bit about this, and it seems not only to make sense, but to be entirely plausible and probable. Most of the theories have pieces that don't make much sense, but the idea I have is one that revolves specifically around the "grey aliens", or the ones that are typically depicted.

What if they're really just advanced, genetically modified humans from (let's say 2,000 years in the future) who are traveling back in time, researching and/or recording history? This would explain the reports of their presence in areas of interest, large events and prominent locations. Instead of having to dig for clues to their history, they could simply travel back in time and physically watch the events unfold.

Could this be the UFO's near the world trade center around 9/11? The odd lights that were reported when the titanic sank (which they thought may have been a rogue whaling ship)? The reported UFO's during nuclear testing? Earthquakes and tsunami's where UFO's have been reported before, during or soon after?

What if tptb already know this? What if that's the highest illuminati secret? What if aliens are really us from the future, and with that discovery/knowledge comes responsibility to deal with it? What if the aliens are against the current human rulers because they are trying to change the timeline of the future????

This would also explain the use of telepathy to speak to us instead of with language, as there are many languages on earth and in the future they all advance into a single language; telepathy.

They could have came here earlier this century and given us technology, by using human looking aliens to invent things, or by other means. Maybe we had fallen behind, so they gave us some key inventions to move forward and stay on track, but tptb harnessed the technology and used it for evil instead of progress?

There's a lot of ideas to throw around with this, from many different positions. Just the genetics and/or appearance of the typical alien would make sense when you consider what would be ideal for radiation, high speed travel, interstellar or interdimensional travel, etc.