First thing to do is to remove the emission shader from the setup! The material you’re trying to make is not emissive, it’s just reflective! And therefore, the glare intensity should come from the enviroment and not from the material itself.
For this type of materials, I normally use a similar setup as this:
The lightblue node is used to control the scattering of the glitter. Low values make the glitter very soft and compact, high values make it more scattered.
Thought this is a simplified version, some other improvements and details can be used.