How many misses does it take to screw in a lightbulb? As they say, you can't miss fast enough.
If you can point shoot something 20 feet away in the dark, good for you. If you aren't training with your pistol regularly enough like most people, good luck with that. Do this for me: Spend a few minutes shooting a 1911. Just a couple mags will do. Next pick up a glock, close your eyes and attempt to point it at an object 20 feet away. How'd that go?
You really can't argue against a tac light or night sights on a defensive handgun. If it helps you get more hits and you can afford it, why not? If you're having so many problems with contact shooting, perhaps you should employ a taser, blade, or some other weapon. Pistols are underpowered anyway.