You shouldn't pick a breed based solely on looks. Malamutes, Huskies etc. look nice but they are built to pull sleds in sub-zero conditions for many hours a day, not as a house pet in a flat in London.
I may be biased due to past experience, but I would personally choose a staffie (yes, Staffordshire bull terrier), for the most part because I grew up with one of this breed (from the Kennel Club). He was two years older than myself. He was such a loyal and daft dog, he almost felt like an older brother. I could go into all kinds of stories, and have such a good laugh and cry about him. He was definitely a much-loved and irreplaceable 'dafty'.
Time to be very biased here!
Either- Labrador-Collie crosses ( Had one that lived to the ripe old age of 17... such a sweetie! RIP)
Rottweiler-Alsation-Collie crosses (Awh. Such a beautiful overprotective mutt)
Or Boxers ( We have the daftest white boxer ever... such an ugly mutt sometimes, but so very hyper)
Or any form of dog. Especially if it looks all wolfy!
I was randomly clicking around on the Internet when I found a breed called the chow-chow... It was so adorable like a huuuge fluffy teddy bear. But I'd never actually SEEN one. Then the other day I finally saw a man walking 2 of them in the street.
I can honestly say I almost ran over, ninja'd the guy and nicked them off him!