I need your opinions on whether to put double curtains in a smallish open-plan sitting room

[mumonthenet]

You know the kind...a double rail? Had a lovely dream of layered linen curtains (floor length) wafting in the breeze.

But the room is only 3.7 by 3.7 (metres).

Would two sets of light unlined curtains be too bulky?

Can't decide.