My inks would likely be boring to most. Grey, black, brown, green, even purple, but all as grey as possible. Toned down, yes. Murky, absolutely. Dark enough to be mistaken for black: perfect.
I think of them as subtle.
I don't like sheen. Contrasting under-colour: shudders. Shimmer: ugh, horrible thought.
I did try going brighter for a while. It was a mistake. Gave them away.
I agree with this line of thinking. Subtle is good.
"Dark enough to be mistaken for black": a great criterion. "Dense black": also a good criterion.
My favorite blue: Diamine Presidential Blue. Why? It is a very grey blue. It is perhaps the "brightest" color I use regularly, but it still displays itself modestly.
I recently bought a very wet pen, and I was horrified to discover that Edelstein Tanzanite (heretofore one of my favorites, in the pen I typically use it in) has a red sheen. It has now been relegated to second-tier status (replaced by Waterman and Pelikan 4001 blue blacks), and will be applied in "drier" applications.
I don't mind seeing contrasting under-color(u)rs once in a while, but they start to get distracting in a full page of writing.
I still use bright colors, but a LOT more sparingly than the darker ones, typically for editorial mark-ups and greeting cards.
I want to like Edelstein Moonstone, but I can't decide if it shades too much for most applications. I like that it on some papers looks like pencil.