As similar to a completely different aircraft as is possible, and the other aircraft is already in game.
In reality the Halifax was easier to bail out of, crew having about a 33% higher survival rate when their aircraft was shot down.
On the other hand the Halifax had about a 33% higher loss rate per sortie than did the Lancaster.
Translating to AH, the first point is not modeled in any way or relevant in any way, while the second point likely means the Halifax would be modeled as significantly less durable than the Lancaster is.
All in all, given the high amount of work needed to model bombers, there are better places to put this effort such as the H8K2, He177 or even P.108.