Alright, I basically have two comments that I noticed when I fixed the edges.
First off, this detail at the jaw will be extremely difficult to pep.
While the detail might work in a 3D program, it will not translate well to a paper model. Paper isn't that flexible, and it will most likely warp. Also, when you have a bunch of flaps there, it means the thickness really comes into play. Paper might be thin, but layer upon layer does make for a lot of material.
My second comment is about the general shape. I'm assuming you want to make the model movie accurate here, so this might be redundant info, just ignore if it is.
If you look at the top of the helmet, there are a lot of bumps and grooves.
You can see that the sides are not straight, but rahter in a zig-zag kind of pattern. The green lines are spots where you will have valley folds, meaning it is actually an indent in the helmet. Again it is not really easy to see when modelling, but it definitely will show in your pepped helmet. If you spend a little more time on smoothing the model in 3D, you will spend less time with bondo/sanding to get a better end result.
Other than that, the model looks great.
