Dude,
It came out okay, but a few points:
1. You don't have a sight channel. Could cause drag problems or if you have night sights, the front post will fill up with material. If you are using the original poly front sight, it could get ripped out - if that is indeed a Glock. Sorry. It's a Grock. I was focusing on the holster, not the gun.
2. Without a tensioning mechanism, the pistol will not fit secure enough to eliminate rubbing and moving around in the holster, causing wear to the finish. Yes, Kydex will wear a finish - even Glocks.
3. Having a divot for the trigger guard as a "locking method" will cause some draw issues with the light attached. Undue wear, and possibly damaging the switch assembly for the M3. I have seen M3 switches break off. Without the light, it won't be as secure.
4. Loop belt attachment. No offense, but this is the worst possible belt securing method. If you pull the loop away from the holster to get it over the belt, over time it will stress at the top of the loop and snap. A certain holster company in Phoenix uses this type of loop and they break often and quickly. A J-loop works much better and has almost no stress involved if you do it correctly. I have many holsters in use for the last 3+ years that have zero problems so far. As thin as that loop is, it will snap at some point.
5. Due to having no tension screw, your firearm could get pushed back out of the holster and get trapped by the trigger guard or light assembly. If enough force shoves your pistol back against the top of the slide, it will force itself out of the back of the holster. I personally hand bone mine to give it more detail and that keeps the firearm secure in the holster.
Good try and keep experimenting. I have been making Kydex holsters for the last 4 years or so. For IWB holsters, I use .093 thick Kydex. For paddles, drop Tac holsters or belt slides I use .125 or .1875 Kydex. I also use the good Kydex, not the Kydex 100 that is cheaper and more brittle that other companies use, like a certain company in Phx that works out of a certain east valley indoor gun range. A 4' x 8' sheet runs me $125 per sheet and more if thicker. It is not cheap and making one holster is not worth getting a sheet for. I get mine from a plastics supply shop.
For ones and two's, give Newt Livesay a call at Wicked Knives. He sells small pieces of the good Kydex and is a wonderful man to deal with. I've known him for years.