First off, I must SQUEEEE because I absolutely LOVE Mortal Kombat, and I don't think it is cosplayed enough!
I think the costume looks great! The only 2 suggestions I would make would be
1. Since his outfit is rather simple, I would look at putting the 'decorative' lines down the edges of all the pieces, it'll help give it that 'pop'
2. I know you said the mask is still a work in progress, and it looks great as it is, but please tell me you're going to do the little mouth part with all the teeth? Cuz that would be amazing <3