I wish that Steven had..

Set up David and Emily meeting... knowing what David does and that she'd prob fall for a "sensitive painter." Because then it would have been more clear that Steven was wanting Emily killed for her trust fund because his business was failing-- not because he cared she was cheating.

It would have been an interesting flashback scene of Steven somehow getting them to meet one another and fall for each other, and then telling David he wasn't the only one who planned on him meeting Emily.