I'd recommend using multiple coats of a watered down paint to bring out the details/crevices. I have a Wave Serpent painted Dark Angles Green, and the crevices are Skorpion Green.
I'll probably post pictures soon, but it looks very Tron-esque. It was super easy to do; I've received a ton of compliments on it, and I only have two colors on it so far! (It's a WIP)
As with your Fire Prism, your Farseer is well painted, and there's virtually no way we can "criticize" your "terrible painting."
All I can say is that on both models, all that black is a little boring. If you're doing it for fluff reasons (a stealth strike force, or from a shadowy Craftworld or something) then it's alright, but otherwise I'd throw a contrasting color on there somewhere.
Also, you might want to post your army in the Painting Hobby sub-forum, they could give you much better advice there.
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