I've already mentioned in chat that both videos are very cool, with much good to say about them.
As a practical matter, I suspect that the first one will be of limited effectiveness as a trailer. Or rather, it will have a specific role to play in promoting ZK, and that role is NOT as a primary attractor. First, it's too long for that. Second, it's too hard for anyone who doesn't already have some knowledge of Zero-K to understand what's being shown.
I think its role is as secondary material for a potential player to find AFTER they have already gotten exposed to ZK in some manner AND they have had something pique their interest to learn more. Once they are at that state, then KR's gameplay features trailer will serve to deepen their interest and excitement in this new game that they've found. But I don't think it serves well as an initial entry point.
It's still an excellent video, mind you. Love it.