I have a similar situation in my dining room. I have matched double hung windows, but one is jammed into the corner to make the front of the house symetrical.
I had a LOndon blind on them for a while and now have panels with the finial removed on the wall side/
I think the idea of leaving the finial off of the corner end is a great one but maybe choose something with a lower profile finial because the large balls really draw attention to themselves and make it more obvious that one is missing.
I would get a different rod with flat/square finials. I don't really like how the blogger's looks - my eye is really drawn to the one finial. With your curtains, I think it will be even more obvious because of the rings attaching the curtain to the rod. You will see your rod even more. With the blogger, at least those curtains cover up the bare end of the rod.