Maintaining Consistent Grain/CA in Global Comp Templates for Freelancers?

Hey everyone, I'm Yuki, a VFX artist currently tackling quite a few shots on a feature film. We're dealing with a range of footage, some shot on an AMIRA, some on a V-RAPTOR XL, and even a few pickups from an ALEXA Mini. The director is really leaning into a specific 'vintage' look, which means consistent grain and subtle chromatic aberration across all comps.

My challenge is creating a 'global comp template' that factors in these elements but is also easy for multiple freelance artists to integrate effectively. We've tried a few things: baking in a generic grain plate and a CA node, but I'm finding that when the freelancers start layering elements, it inevitably gets tweaked or even bypassed, leading to inconsistencies. I'm also seeing issues when different plates have varied noise profiles straight out of camera.

How have you personally adapted a 'global comp template' with elements like grain and chromatic aberration to maintain a consistent look across shots handled by different freelance artists, especially when working with varied camera sources?