Okay - here's a brief praisee.
An episode of Casualty contains 60 scenes.
It also contains 3 Plots-of-the-Week (a,b,c), plus 4 Arc-Plots-About-The-Regular-Cast.
A,B, and C will get about 10 scenes each. C, the funny one, will normally have less.
Regular plots 1-4 will get about five scenes each.
You have ten scenes left over to zip the show together.
On a good week, Plots A,B,and C will resonate with a central character - eg allowing an aspect of Charlie's character/current situation to be shown/echoed.
So, if a regular is pregnant, they should somehow resonate with an A,B or C plot.
For each A,B, or C plot, there should be a maximum of two scenes set-up (eg Knives! Blood! Arg!), four scenes of medical trauma, and then revelation through conflict (in this week's episode, a gay bashed Christian earns the disgust of his vicar and the love of his boyfriend).