I assume there must be some point in introducing these characters and then dispatching with them 10 minutes later. Agree that Lady Agnes' outburst about Lotte made no sense whatsoever; whilst keeping basic facts of all foreign affairs straight it can hardly have been difficult to remember what was kicking off in Nazi Germany, surely?!
Not clear at all where Rachel appeared from, nor what the references to her husband were in aid of. Shame not to explore her back story as a university lecturer more.
Agree that the footman thing was a total waste of time unless he's coming back. Plus if you were his mum, would you think a life in service to a bunch of martini-swilling aristos was the right place for someone with an alcohol problem to rehabilitate?
They're simply trying to cover too much in a three story arc. Today we have the abdication crisis - it's all too much political history rammed into a social drama.