Our choices were similar to the op, but I opted for the much more common 9mm, and opted to train my wife on semiauto pistols. That has worked in our favor. We prefer inexpensive Taurus pistols, a PT92 for myself, and a PT111Pro for my wife.
I had to concur with the Mossberg 500 12 gauge, and also heartily endorse the Spec Ops recoil reducing, 6 position stock, especially if you intend to provide the weapon to a person of smaller stature, such as my wife. She handily fires 00 buck without flinching and without devastating recoil that prevents a follow up shot.
I also went for the rather venerable and definitely incredibly common and available ammo, 7.62x39 for our initial rifle caliber. My AKs are rock solid and fit with my training and with my capabilities nicely. The less expensive ammo has been a huge plus over the years, allowing much more range time than would have otherwise been available.
I also filled a different niche that the OP misses. I can't stress enough the need for .22 caliber rifles and pistols. These incredibly versatile weapons will serve so many purposes, at such a low cost, that I cannot believe the op completely missed them. With .22 rifles, you can easily become proficient at taking small game and pests (fox and smaller) at up to 100 yards. With .22 pistols you have a convenient, ethical and quick way to dispatch small farm ready domesticated meat producing animals, such as rabbits. 5000 rounds of ammo for this weapon can be had for less than the cost of a nice meal at a nice restaurant. You might fight once a day, 5-6 days a week, if you train with martial arts or something similar, but you'll be sure to eat at least 3 times a day. You want a convenient, inexpensive way to take game, and you want to understand it well.
I received a wonderful gift from a relative, a 30-30 lever action, that I outfitted with a scope ballistic corrected for 300, 200, 100 yard drops, and the appropriate new leverevolution ammo from Hornady, which fills a nice hunting niche to 300 yards.
With all of the above out of the way, I am constantly looking for a good .308 bolt action to fill my last niche, which is the true long range rifle.