Working on that painting, finally. Got a more complete sketch. Ready to start painting, now.
I've got his outfit established as a long-sleeve t-shirt (brown, with dark-grey patterning and silver decals/lettering) and ripped jeans (maybe a pale grey-blue), with holes at the elbows and knees where his spikes protrude, with the armor a mix of leather and plate pieces.
The leather is going to have tooled lettering that will glow red from enchantment. The greaves (shin-plate) is going to be metal plate with leather overtop, with the horn-shape a polished fitting that pins the leather. I just had the idea to repeat the horn-shape on the greaves on the biggest plates, on the bracer and pauldron. (just did it in pencil. Looks really cool. :D)
I'm also going to put silver on the edges of the various plates to clarify that they're all leather over metal. (I'm thinking of the Rohirrim armor from LotR, they used tooled leather fit over the metal plates to decorate it. It's also practical for long-term use, it's easier to tool a new piece of leather than to re-etch a metal engraving after repairing the armor itself.) In-story, it would also be a clue to differentiate between true Kin who need the armor, and poseurs who just get shaped leather for the style of it.
For his skintones, he'll have sort of a ruddy tone around the scales, but be pale, otherwise, and his horns and scales (which will also be on the knuckles same as the feet) will be a shiny black. Still debating on his hair, either black or red. (considering the way everything's layered, it'll probably be one of the last things I do, to allow it to tendril over other objects.)
Edit: 11:19pm
Got this much done in one night, heading to bed. I've gotta get up tomorrow for class at 6 in the morning. (eugh.)