Flashlight change
When using the flashlight it's hard to know when you're blinding the killer and it's also very easy for the killer to avoid looking at it by just turning side ways. So, Instead of a flashlight a torch would be much better tool. When it's in use it lights up a certain range around the character instead of trying to aim at the killer.
Comments
"hard to know"
There's a visual cue with the cone getting smaller and smaller, then flashing when you blind successfully, a burning sound whenever you aim correctly and the killer is in the process of getting blinded and a sound cue when you successfully blind them.
You have the tools, use them.
Flashlights are completely fine. It just takes some getting used to but once you learn how they work they're fine.
You shouldn't be just trying to blind them randomly and when they're chasing you. They should mostly be used for when the killer is stuck in an animation and can't move their head like kicking a pallet or picking up a survivor.
As well as the things said above, you get a score event which isn't hard to keep track of
The only problem I've ever had with a flashlight is save timing, because I'm bad at video games. I've never had an issue actually blinding the killer. Also, yeah, the killers are supposed to be able to avoid it by turning.
That's why you have to time it.