Shane
YouTube Network Addict
Channel size doesn't really matter unless comparing to a channel in the Google preferred - top 1%.CPM is probably low because you just aren't that big of a channel, and your not doing content that can be promoted well.
I'd say it's more low watch time coupled with double trailering (what I mean by this, is that not many brands would want either their ads to be served on or to pay much money for their ads to be served on what is pretty much another ad or trailer for another product) Trailer channels to tend to have a low cpm in general.
On another note @OP, this is copyright.
You can't compare yourself to bigger channels like say VisoTrailers who have likely acquired permission for this upload.
Unless the trailer is licensed under CC or comes with a free re-distribution license you cannot just re-upload it as your own and especially not try to make money off of it.
But I would be very surprised if some of the film/ production companies have not content id claimed one of your videos before so you probably already know this.