I would suggest getting a Glock for a pistol. Either the Glock 17 or Glock 19, depending on hand size.
I have carried the Glock 19 daily for two years. While my hands are large enough to have a small part of my palm hanging below the grip, it’s not enough to be bothersome, so YMMV. Yes, I do find the G17 to be more comfortable to shoot but for carry I find the G19 easier to conceal. For the record, I own both so I’m speaking from experience.
I have over 10,000 rounds fired on this G19 with not a single hiccup. No joke The only thing I have replaced on it is the recoil spring just for preventative maintenance. It was still doing fine at 6,000 rounds when I replaced it.
I have taken it through 3 firearm classes, two pistol and one rifle, and have shot several IDPA matches with it.
For rifles, I’m partial to the AR. Nothing wrong with the AK, but if I could only have one it would be the AR. Pick up a quality 16" AR and it will cover 95% of your shooting needs when push comes to shove. I have a 10.5" AR15 with a supressor and 16" AR and they both run great. I’ve got ~5000 rounds through each rifle. I shoot a lot. I test my weapons. I don’t run two mags through them and then deem them reliable. Running a firearm hard will test it in ways that just target shooting can’t. On that note, I wouldn’t recommend the XD as it seems to not hold up during pistol classes. After the Glock I would probably pick up the S&W M&P9.
Most importantly, take training classes to know how to run your weapons effectively.
ETA: Like someone else said, go to AR15.com and spend a few DAYS reading the info on that site. Yes, it contains that much info. Don’t get all your information on a forum that is dedicated to something else entirely. There are lots of misconceptions with firearms floating around out there. The sound of a shotgun being racked will scare burglers away? Laughable. 20GA may be better than .45ACP for HD but only because long guns > handguns. The 20GA is still far from desirable from HD duty.
Good luck with your decision!