I still think blinds at the bay window would look better, you can use a thick fabric and have a thick lining put in as well. I'm not so sure that hanging curtains from the crown detail would look right above the door.... I'd be more inclined to go from the picture rail height..... just personal opinion! Also, what colour are you thinking of doing the walls and are the window coverings likely to be heavy patterned or plainer textured fabric? Just thinking that if the walls were say a beige then a darker shade for the window coverings with a slight pattern or texture it would be less obvious that the windows were different heights, your eye wouldn't be drawn to it so much as a heavy pattern.

I think that is a double-track and they have a second, heavier curtain behind it. But even if they don't, I think that is what you should do for versatility and look. They actually have it built into the frame so it is hidden and super sleek, but I think you can achieve this look if you run it along where the angled ceiling meets the wall. I would take a picture of your room and what you like to John Lewis, or another high end store or specialist curtain maker and ask their advice for specifics. I was just trying to give you an idea that I hoped you would like! I'm sorry I can't be super specific, but I think you need to have these custom made to do justice to the room, the view, and to get exactly what you want.

I think some beautiful white voile for the day time, mounted on a very discreet ceiling mounted track, such as Silentgliss, which can be bent into the bay. I would then put a bay pole in front of this with whichever curtains go with your scheme, using a blackout lining. I would be careful not to have the curtains gathered too full though as you do not have a lot of space to the left of the window to pull them back. Although unconventional, to overcome this problem, you might want to consider having the curtains made to different widths, ie a shorter left curtain and a wider right curtain so that when they are closed they meet at the corner. On a flat window this would be very conspicuous, but your window is unusual.

Going with a roman blind would be a good choice, the soft fabric won't look out of place next to the curtain - https://www.makemyblinds.co.uk/roman-blinds/