I think that the plastic bent because its from the original Dark Eldar frame in the 3rd Edition box... the newer plastic never has that problem.
The hooves are smaller than feet, but thats partly because hooves are smaller than feet! They may be too small, but hooves are really a quadruped thing, and most quadruped mammals have small surface area to their feet - in part because the ankle extends upwards.
I can't actually separate the canisters, as they're a single piece - And its a Chemsprayer, not a flamer

So sudden promethium explosions are unlikely.
A belt is possible, though...
And for the three or seven, he's got three large pustules on his swollen belly for a reason! And they'll be picked out in a bright colour (yellow most likely) if I paint him dark and rotten, or a dark colour (a purple perhaps) if I go for pale and sickly.
And yeah, its a ruff. Inspired entirely by one of John Blanche's Chaos Marines, featured in the Blanchitsu that was put on the White Dwarf Archive a little while ago.
One feral mutant is already built, using only the spawn box - another is WIP. Now for some requests - I need some inspiration for Slaanesh stuff. I need names for both the Slaanesh marine and my upcoming Slaanesh cultist, and ideas for how to make the cultist look. I'm thinking some sort of depraved toad thing might work. I kind of want to steer away from the slender beauties with crab claws and leather a bit, and go for something more repulsive...