Size and complexity are definitely ok.
However, he looks like... well, how shall I best put it - like simply a pile of parts come alive. He needs some more coherent textures - there's just too much stuff sticking out everywhere.
For the moment I'd suggest you focus on redoing the lower legs with better ankles (the leg-foot connection looks really awkwards here) and try coming up with a better head and neck. Creative use of parts, I admit, but using the orignal head of the mask with its face on it just doesn't work. Got me thinking, though... If my idea turns out to be any good I'll tell you.
Also yes, more red.
So about that idea for securly connecting that mask to a custom head:
Build this and put the horns through the eyes of that mask.
Connect them with this t-bar piece. I'll leave everything else to you from there.
Rules and list in post 1
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