Wow - this is really supposed to be a SLAANESH-Terminator? Where's the beauty, the passion, the weirdness on this one?
Sorry, but he looks like a Black-Legion-Terminator with a lot of headache.
If I were you, I'd paint pearts of his armour pink or at least purple to show he's a servant of Slaanesh.
And... am I growing blind or stupid - or did you really use an imperial assault cannon with a daemon's head as a "blastmaster"?
I really don't want to p*** you off, friend, but this conversion is not too good at all.