Mt. Hood for the Hallertau Mittelfrueh derivatives. I also like the rest; Liberty, Crystal, Ultra, Vangaurd. Agree that Crystal is citrusy, but I like that one to make a lager with an American twist.
Sterling is nice if you want a spicy noble derivative, it is from Saaz.
Played a little with Santium, it is a Tettnanger derivative.
Northern Brewer? Never heard that called Noble and it was bred in England.