I use strictly bulk 124 gr NATO because it isn’t watered down like the cheap 115 gr target ammo and it feels exactly like what most defensive loads feel like that aren’t plus P.
As far as POI and POA, unless you are shooting that Glock at over 25 yards, you will not notice it no matter what grain you choose. Most people do not have the skill set to notice that anyway especially on a non match grade pistol at around 10 yards.
I agree with C3D, plus, the act of practicing will make you a better shot over any ammo variety at pistol range. If money is an issue get a good pellet gun or .22. It carries over and in most cases makes you a better pistol shot overall.
My Glock 43 doesn’t like 124 HP. Had lots of failure to feed. They would get caught up on the feed ramp. I switched to 147 and that solved the problem. So I stock up on 147 FMJ for target and SHTF use and have a few boxes of HP for daily carry purposes.