As a new shooter, I would caution you against these kind of "ah-HA!" conclusions. Especially when you're starting out, you're probably going to suck. There's a tendency among all people (I did this for ~1 year, so maybe this is just projection) to try and compensate for every little problem and conclude that it was that one little thing and if only they could do it differently next time, then... Ultimately, a lot of things have to come together to put the round on target. Your grip is a big part of it, but probably not the biggest (being trigger pull). Focusing excessively on one thing, in the hope that it will turn you into a god, often leaves the other parts to suffer, and it's easy to bounce back and forth from one such thing to another (akin to over-steering a car).
All of this stuff is very subjective, and everybody has their own two cents and their own tips and tricks. As someone who has only recently "figured out" handguns, all I will say is this: dry fire, preferably at a non-organic target. Flip on the TV, pick a light switch ~10 feet away, and shoot at it. Get comfortable holding the gun, pulling the trigger, and having the sight not move. Regardless of your preferred technique, I know few people who will argue against the merits of dry fire. Hundreds, thousands of times. Dry fire.