The Bas Lag series. Perdido Street Station, The Scar, and Iron Council.
It's not much like Martin beyond being mature and serious takes on fantasy, but it's a good example of how to do fantasy that's really, really
big on being actually fantastical and yet keep it grounded and lovely and fantastic and the rest of it. It's more like a Discworld that's grown up and gone weird than it is Westeros.
All said, check it out.