I like both First Gold and EKG, they are quite different to me but both go well together I think, even if I mostly use them as either or. EKG with BX is a very nice combo. I quite often use Fuggles, Challenger and Northdown, and also been trying some of the "newer" British hops. Of the latter I've really come to like Harlequin, most of the others haven't made a lasting impression.
I'm not sure what make PUB go marmelady, I have had different experiences with it. I usually start fermenting low and after a day or 2 I let it rise. Sometimes I get some marmelady notes, not strong, sometimes not.
I agree with the American hops, I often taste cat pee or onion... it's a shame, the few times I don't get it they are great though.