The advice from Flytyer is very good.
I can understand where you are coming from. I have suffered from the same syndrome.
The problem only really becomes apparent when you start fishing.
You have a box full of different flies, which fly do you choose?
You find a fly that works and then you either lose it or a fish destroys it, what do you do now?
By all means tie variations but make sure that you have enough of each type.