I really like the Special effects paints and Nihilakh oxide should work really nicely on the Minotaurs. If you think they are too bright possibly try making a slightly darker mix instead for instance I generally use a really thinned down mix of Hawk Turquoise and Caliban green but the rest of my brass is generally quite dirty anyway (I mainly use it on nurgle models). Also try using Blood for the blood god on the weapons to create some bloodsplatter.
Me: To be honest im amazed there isn't a chaos god of not revising or at least chaos god of procrastination
MidnightSun: There will be, when enough people do it. Y'know when the Eldar were all engaging in their hedonism and Slaanesh ripped open the Eye of Terror with his creation? Slaanesh will have NOTHING on the God of Procrastination, and his vile minions will carve the galaxy asunder in a thousand year reign of blood.... Tomorrow