Brook. O'Maisom and Etches have all been mentioned but the top man at their gym is Kid Galahad. :good
At the moment for me the prospects I'm most interested in are BJ Saunders (in a tough division not only across the world but also domestically) Frankie Gavin (nice to see a UK boxer with such good technique) Kal Yafai (still early days, shame about the injury but could be the only one fast tracked of any of those mentioned here)
BJS has got everything needed to be a future world champ. Hopefully being a traveller won't prevent him from having a permanent gym and trainer. He really does look like our best prospect if you discount the likes of Kell Brook and Tyson Fury who are probably now contenders.