The basic shape is spot-on.
Hmm, I hate to be "that guy", but yeah, it looks like it might make a good bomber... but for the fact that the airframe requires complete internal and external redesign. I did a bit of thinking about this, as ya do and I came to the conclusion that you might as well start from scratch with an entirely new design.
The Ensign airframe requires a complete internal remake, everything needs to be redesigned. Where are you going to put the turrets? the nose and tail needs redesigning, the bomb bay needs to be incorporated below the wing box, and is it going to be below a false floor or just the open fuselage below the wing box, which requires extra internal strengthening? And what about the wings? The centre box spar the Ensign wing is designed around is five feet deep and although the rear half internally was metal, it's covered in fabric. The Whitley was the same. The tail has to be redesigned to incorporate a turret and perhaps the vertical fin has to disappear to become a twin tail, like the Whitley and the AW.23 before it.
Turrets require redesign on the structure to support them, as well as a beefing up of the hydraulic/electrical system to power them. I'd also put either Nash & Thompson or Boulton Paul turrets throughout (The Whitley had AW unpowered turrets to begin with then went to powered N & T in the tail first - the all-powered turret armament didn't appear until the Whitley V) except for N & T top turret prewar, because you'd end up with the nasty FN.7, which was slow to rotate, caused aerodynamic issues on existing types and was generally disliked by the gunners. The top turret fitted to the Lancaster doesn't make an appearance until later. As a result of this extra strengthening and weight and complexity, we are gonna need to beef up the undercarriage too, which will require extra work to the frame supporting them as well as the actuators required to lower and retract them, which means work on the nacelles and wing structure...
AW aircraft were very strong because the firm built box girder bridge structures that resembled aeroplanes, but the performance of which is impacted by the availability of engines, which sadly a Pegasus or such like is just not going to cut it. Merlins or Hercules' will have to suffice. The thing is, the timeline of our bomber Ensign determines a lot of what it is gonna be equipped with. Let's say it is done to B.12/36 (which produced the Stirling), then either Herc or Merlin, turret armament, probably N & T but with the 'orrible FN.7 mid upper turret. In order to build it, Whitley production is gonna have to take a back seat, which the Air Ministry, having ordered them won't be too happy about but not specifically a bad thing, as in real history, the Ensign development was curtailed by the Whitley design and production, which meant only a few were built and they were late in delivery.
So based on the redesign, establishing production lines, slowing Whitley production (because of manpower requirements, it'll take a lot more guys to build a four-engined bomber), perhaps even a new factory, big four-engined bombers take up a lot more space than twin-engined bombers to build, and trials etc, we are looking at an in-service date of around (optimistically) early to mid-1941, give or take a few months if the Stirling designed from scratch is a guide...
To be continued...