You're right, 'Shelby proximity to dangerous spraying molten metal' is a staple ingredient of most episodes.
I also forgot:
12. Strong woman being strong (Polly / Ada / Esme). This can on occasion be interspersed with a scene where the strong woman is momentarily weak / unsure of herself, but...
Formula for a good Peaky Blinders episode:
1. Cut the Downton Abbey hoity toity rubbish.
2. Cut the quantity of slow-mo scenes backed by too loud, heavy and obscure soundtracks, which frankly cause me to drift off and add b***** all to the production quality.
3. Add more vicious fight scenes...