Actually, even back in electron tube days, the second generation of a system was often lighter and more compact than the original, as long as designers could resist the urge to cram in new features.I doubt the electronics would have been negotiable, but what kind of changes could have been made to the intake duct?
I'm no expert on intake ducting, but my understanding is that the Dog Sabre's intake was not the straight shot down the throat of the compressor that the "open mouth" Sabres had, due to the bend around the radome. Early jet engines tended to be a little fussy about smooth airflow into the face of the compressor, and would sometimes compressor stall or flame out just from the wakes of bullets or cannon shells leaving the nose guns. The early axial flow versions were especially susceptible to this. Sometimes a sudden yaw or the wake turbulence from another aircraft would cause a flameout. My instructor said he got a lot of practice at windmilling relights in the dog.