I notice the colors coming out of my sniper rifle. I mean, you don't?
Crystals were actively usable by every single PC in the game. Don't talk to me about things for companions. Companions are of marginal value at 50. I'm certainly not worried about earning 'rewards' for them.
So, you're honestly saying that non lightsaber users get just as much aesthetics use out of crystals as the classes that do use them? Sorry, but I don't see it. And to answer your question, no. I really don't notice/care about the color coming out of my rifle. My main is a Vanguard and I have never cared. I care about the look and sound of the rifle, but not the color.