I loved the Kite demo and I’m really excited for 4.8 now!
One thing I hope for are the tools which Epic used. I know, that might be too much to be asked for, but things like the script they used in Maya (I think it was Maya) to get the Albedo would be amazing or the ecosystem for planting vegetation and so on. But I guess that most of the tools are Epic intern only, but maybe we get lucky 
At last I do share’s original concerns, I know that most of those games sell bad, but they still somehow end up on Steam and co. (I remember an example which ripped the ShooterGame). But some of the assets might be useful when used wisely (maybe stuff like vegetation, given that you are going for a realistic look). Let’s hope for the best ^^
Greetings,
Dakraid