Looks really good, but it's missing the feathers! All Empire helms must have feathers!!! (just kidding, most of the feathered ones are kinda annoying looking).
Something you might consider adding or creating a second helm with it, is a laurel leaf crown sort of like the ones in this pic minus the feathers -
Or you could just do multiple variations with and without the feathers and laurel crowns (ooo! or little lion/bull/gryphon statues) just to add to the variation without having to design more helmets. I also just realized after looking up that picture, that the guy with the feather mohawk in the back row looks kinda cool too. Just saying.
I look forward to you creating new versions of helms for Chosen, I really don't like the lopsided 'giant fish-hook thru the skull' look that most of the Tzeentch themed helms have. Keep up the great work!