Is the S terminal a mirror of N? In S, NW has a lounge on the gate level with nice tall windows, and I think BA has one that is upstairs from the gate level. Of course, the NW club is significantly smaller than the RCC, but there may be some hope for light!

On a side note, I recall talking to one of the RCC agents shortly after the IFL closed, and she was saying that SEA is one of the most expensive airports in terms of rent; that's one of the reasons there is no longer an IFL. I suppose we should be lucky they don't close the RCC altogether!