Now, before you start sneering, I'll mention a few reasons as to why it might be worth having.
Up to 13,000 LB bomb load
Troops and supplies carrying ability. Infact it would IMO be better than the Goon in the MA because it has some guns. However, the fact that they only had .303s was the main reason they were withdrawn from daylight missions after 1941 so this is no doubt open to debate.The armament being - Four-gun dorsal and rear turrets, albeit .303s. Still useful at close range.
Able to take a lot of damage and still get home.
It would also help to balance the British - American bomber ratio.
My main reason for suggesting the Halifax, is the dual-role capability mentioned before. The fact that it could be used to carry paratroops and supplies or go on bombing missions and to add yet more choice in the hanger.