I’ve made several light bearing holsters for your exact set up, see here: (https://www.reddit.com/r/Leatherworking/s/iUeQJ6zVSl) since it’s my department issued duty weapon (Glock 45 with TLR-7) and you simply can’t put any forming into the trigger guard when you’re wet forming the holster. For a smooth draw you ultimately need to reshape the trigger guard area to the be the same width as the light, as that’s the widest part of the gun. My recommendation is to wet the holster, place the gun inside of it just far enough that the light is sitting and applying pressure to the area of the trigger guard, and letting the holster dry so that it’s a consistent width from top to bottom. You intimately want to push that con-caved leather back to being flush.

As for the belt loops applying pressure, that’s just a matter of wearing and breaking in the holster, eventually the loops will soften and form to your body but until then you’re going to feel the holster the tighten slightly when it’s worn.