I do this for a living....so let me preface by saying you are about the millionth person who has ventured into the first steps of shooting a handgun.
First and foremost, get the pistol that fits you the best. Don't buy other people
s Bs when they say that "X gun shoots best for you, you should get X", take advice and experience, but judge for yourself. IMHO and from observations on the range during training...adjustable sights have absolutely no place on a CCW or duty gun. Get a good set of fixed sights that offer you the same sight picture during the day as they do in low-light environments, I like TRUGLO TFOs or XS 24/7s and work on the following:
Second, you need to work on your sight picture and trigger control. People telling you to adjust your sights are giving you a solution for a non-existent problem. It is NOT the pistol...it's you. Your eyes should be focused on the front sight before you squeeze the trigger. Work on dry-fire practice drills. Ensure you are pulling the trigger with the first joint on your trigger finger, and that it is one consistent pull to the rear...not a jerk, not a slap, one consistent, smooth pull to the rear. Some people refer to it as a "press", that's fine too, as long as it's consistent and smooth. The sights are not off...I've shot a 19 in a class with no sights on it, and still consistently hit the 10 ring at 10, 15 and 25 yards at varying speeds to prove a point about sights and trigger control. It's taken me a long time to get to where I'm comfortable and confident making the statements I make, but I promise you, it is true.
There will be a pistol that "fits" you best, that's the one to get. But make sure you focus on those fundamentals and it will make it easier to determine which pistol fits you.
The other thing to pay attention to is making sure that whatever grip (it doesn't really matter if you hold the pistol with two fingers, or all ten), is consistent. Don't change in between each round to do the newbie "I've gotta see where that one went" look. Take your firing position, squeeze off five rounds with the same, consistent focus-on-the-front sight sight picture and smooth, consistent trigger press/squeeze, and then check out your target.
If you're ever in WA, swing by our range, I'll gladly work with you until you're in the 10 ring! (Or if you want, shoot me a PM and I can give you some drills I do with students to work on those things)
Good luck...oh, and BTW, with the focus on the front sight/steady trigger press or squeeze thinking, I can shoot ANY pistol to the same level of proficiency. Some makes and models don't shoot as comfortably as my 19, 21 and 26, but the same level of accuracy.
Anyone who thinks I'm full of the brown stuff is more than welcome to test the theory out...it works, I promise. It really is about trigger pull and focusing on the front sight...not about the gun.
Good Luck!