At the ranges presented, instinctive shooting is about all I would need - and a 12 bore with GOOD slugs would be the go-to gun - for me.
When training, we taught our guys to hold a 6" group at 25yards shooting instinctively. My riot squad could all do that. I taught "Big Ron" to do this with his 8 3/8" M29 with factory duplication loads. Gun held at shoulder level, just looking at the centre of the target, no sighting.
It only took 45 minutes of one on one training for him to accomplish this. Afterwards he said:
"I thought this was impossible, you were just blowing smoke. If I hand not just done this myself, I would not believe it."
Having a greased "metal-man" surely helped speed up the process.
I noticed most of the instinctive/pointing shots landed high and/or far back. That is common without 'some' practice at this type of shooting. Hip shooting makes shots land even higher for most people.