Just checked the bombload for the Wellington, typical load was only 2,500lbs max was 4,500, going to rule that off my list.
4500lbs is more than the B-25, more than the B-26, more than the Ki-67, more than the G4M1, more than the Boston Mk III and more than the A-20G. Of the twin engined bombers only the Ju88A-4 and late war Mosquito Mk XVI can carry more. The B-17G only carries 6000lbs.
What are you expecting for a 1940/1941 bomber? The Beaufort you posted the request for only carries 2000lbs and doesn't have the defensive firepower nor the reputation for ruggedness that the Wellington does.