The mission order for Stubbs Dirty Laundry is completely random (calculated as soon as you first call Angus for a job) and cannot be predicted in any way.

On When The Blue Chips Are Down, the final cutscene can be skipped as soon as it starts, but only when there is no audio file playing. The fastest cutscene skip is frame perfect (or close to it). More info on this here http://pastebin.com/LuQriQiU

On First Impressions, you can kill the congressman by aiming through the window outside (You'll know when to shoot when the aiming recticle shows his health)

On Phone Ho you can push the first two hookers to scare their clients and spawn the next guy earlier:

On Phone Ho' the hookers you need to distract are the one on the far right side that walks around the corner when you trigger them and the one on the far left side standing on the sidewalk next to the street. These two also shouldn't follow you and dont need to be scared off with a gun.

You dont need to keep any distance to the customers/target. Make sure not police patrol is around when you push them since a wanted level with scare them off and lead to mission fail.