If restaurants in London still allowed smoking, I could see that place becoming a family favourite/regular hangout and whiling away lazy Sundays there with newspapers and good conversation to round out the great food.
But, having to walk outside and smoke in the street is a real bummer. So my regular Sunday brunch venue will remain at home - especially if we get approved for the flat in Chiswick we're hoping for. The flat has a back garden as well as sufficient space indoors for genuine entertaining and civilized dining so with a bit of luck, BBQs and dinner parties will be in my future once again.