Research and planning- cast selection/de selection

For our trailer me and my partner have thought about who we should choose and who we should not choose for the trailer, because after our first trailer shoot we have found out that the actors are not taking it very seriously for example using the right acting skills and facial expressions, however their were some actors who were doing really well, so we decided o pick less people and also picked the actors that would take it seriously.
The things that are crucial in our horror genre trailer is

• Body language
• Movement
• Acting skills
• Facial expressions
• Attitudes