Interesting project you have going there, congratulations with that, hope everything turns out well.

Just out of curiosity do you plan on it being a physical book or both?

Not sure if its to late or even your intention with the trailer, but obviously im speaking from the point of view of someone that first learned about your project, so these are my initial thoughts. After watching the trailer im not really that much more informed in regards to what is going on, meaning I know its a story of some thought, but im only presented with some visual information in forms of the images in the beginning and the video, but not to anything regarding the story it self. Which i think is unfortunately since you say its a science fiction story, so assume their is a plot, some main characters maybe some evil guy or organisation or something. So at least to me, I think you would sell the project and the story better, if you introduced these things through the trailer. For instant:

An ancient alien device is found, which can destroy a whole solar system and is now in the hands of some evil people, and its up to the main characters to destroy this device, before they can figure out how to use it.

Lets assume that was my story.

1. Then I could start the trailer with showing some evil guys standing in front of some weird alien looking device and talk about how they would be able to rule the universe once they figure out how to use it. Might not even have to be clear what the device is.

2. Then switch to a view of the main characters and introduce these and present some of their traits, which makes them unique and to simply get viewers interested in them. Maybe what they do, are they mercenaries, special forces etc.

So you build up interested with the viewer through the trailer, so in the end they want more :D

Anyway this is an example of what I mean which I think does a pretty decent job of getting people interesting in what its all about, this is movie trailer from a computer game called Mass effect - Andromeda, obviously these are highly professionals, but what I think is interesting about it is the way it introduce or build up the story of something that is clearly wrong or have gone wrong.

Cinematic trailer Mass effect - Andromeda

Some general information about your book could also be nice to have, such as number of pages and so forth. Maybe in the youtube description make a direct link to you webpage as well.

Anyway great work, know its a lot of work and as I said these are just my initial thoughts from someone that knew/know nothing about your story or project.