Hmm, I prosonaly paint the frozen stars and the twisted path but I would think that I would use Arihman blue mixed with some green to make it a better turquoise for the job.
for the red I would work up in the base, shade, layer, highlight process of khorne red,caraburg crimson, thinned Khorne red and the wazdaka red as highlights to give it a slightly lighter tone instead of the lighter Khorne red,caraburg Crimson, Wazdaka red, Wild rider.
For the gold use retributor armour, Reiklen Fleshshade, Liberator Gold, Stormhost sliver.
Silver should go Leadbelcher, Nuln oil, Thinned Leadbelcher stormhost silver
for the white bits base in celestial grey and edge highligh in white scar.
Just a few suggestions, take it all with a grain of salt because I'm not he best painter and I'm just throwing ideas out there for you