Gentlemen -
I must put forth a completely different line of reasoning for Royalty's request.
My recommendation would be for an AR-15. Here are some of the reasons why:
1. People shoot better with a rifle than with a pistol. Pistol skills are much more perishable than rifle skills
2. A pistol is what one uses to fight their way back to the rifle they shouldn't have laid down to begin with. (Clint Smith)
3. 5.56x45 breaks up better when passing through walls vs. 9mm which just punches through. Royalty did not state if he has kids, or lives in an apartment or on 160 acres, so I don't know if pass-through is an issue. It is also a substantial upgrade in power from a pistol or Pistol Caliber Carbine (PCC - why carry and use the size envelope of a carbine for a pistol cartridge's effect on the target?)
4. Any 12-13 year old and up can handle the recoil impulse, so if Royalty goes down, Mrs. Royalty can step in (assuming she was trained and of proper mindset).
5. The carbine/rifle allows Royalty to defend himself out to 500 yards, whereas a handgun is only good for 50.
6. Lego/Barbie doll nature of the ubiquitous platform - he can get it tailored to his body shape and Goldilocks preferences. Mags, parts, ammo (normally) are available everywhere.
7. 29+1 rounds of ammo beats 17+1 for the G17, and 5-10 for the shotgun. Reloading is at least AS easy as the Glock, and WAY easier than the shotgun. If the shotgun takes mags, then 29 beats 10 rounds.
8. 85% of people shot with handguns survive. Rifles are much more decisive fight stoppers. If Royalty is repelling boarders (an ANTIFA squad, or just 4 miscreant home invaders) then this becomes a genuine issue regarding stopping the attack of the first bad guy to be able to focus on 2, 3 & 4.
9. With rifle he steps up to becoming a minuteman and can help defend the US. With a pistol he is better than a liberal, but not fully up to speed.
10. The carbine route doesn't even have to be 5.56 - I prefer .308WIN, there is .300 Blackout, .300 Hammer, .350 Legend, etc..
BTW, the G-17 is awful large to carry concealed, whereas a G19 hits the sweet spot between CCW and being able to ride the bucking pony during shooting. If it was JUST a nightstand weapon, then the size won't matter, but if you only have one pistol, it should be concealable so you can defend yourself away from home.
I have a few ideas in this area at hammers4hunting.com. I have taught CCW for MO for over a decade - NRA instructor, some time with Uncle Sam coaching marksmanship teams, etc.. I am not saying I know it all, but have been taught by **NOT**PERMITTED**, Clint Smith, Suarez and Uncle Sam and try to share what those parties pounded into my rock-hard head. My military background overrides plain hunting/the civilian approach. It is, at the bottom line, after all, combat we are talking about. Hopefully Royalty will examine the carbine route.