Quote: "big, brash and bustling'"
Surely that rules out the Olive tree? It is all of the above IMO.
Most of my suggestions would not be posh. Sous Les Nez used to be excellent, however I haven't been for a couple of years. Mal Maison's restaurant might be worth a bash, but I've not been there for a while either.
I don't like either Brasserie Blanc, or BiBis (sp?). They're both tosh, however Brasserie Blanc was nice and relaxed, and farely quiet, but the food was average for the price.