I can not understand how people are calling the cast weak. I don't get it. We have not seen the film yet. All the actors, from what I have seen of them anyway, are very competent at their craft.
The fact that they are not all 'big names' means very little to me.
This may very well turn out to be the best performed and written Predator movie. There is no reason that it can't be that.
Point is. We know nothing of the finished product beyond who is directing, writing, acting and making and all those involved are talented. So why all the negativity toward the cast?
I personally am really excited and have faith that this will be a good movie.