I don't think Lockheed=reliability the easy way, i.e., by design. I'm biased, I was a crew chief on the C-141.
I would love to see a skinny C-17, if it could be done reasonably. Meaning basically a modernized C-141. Same motors as the C-17, maybe derate them to where the temp and P.A. is not a factor if you lose one at v1. Save the core reversing and inflight reversing might not really be needed.
I think that's the size of the A-400M and I think the C-141 was a great sized aircraft. I bet the Airbus folks have screwed up that aircraft by trying to make it do too much like a C-17 with props.
Pull out the stuff you don't really need everyday, like the flap travel and the DLC, keep it a front side aircraft, if it makes sense. Keep the refueling receptacle, if it makes sense, but don't plan on using it much.
If you keep it strong enough to land at max takeoff weight, that's fine, but heavy. Would it need a HUD? Would it even fly airdrop? Might as well- if it could do it frontside maybe the wake issues would be massively lessened.
If you could get the fuel burn down to carry the "typical" 80,000 ish pounds of 11-13 pallets down to the burn of say the MD-11, you'd have something.