It's all about logical and convergent/parallel design. Some of us different artists have arrived at the same design style because they make sense. There are only so many nice looking shapes you can make with a helmet visor, and sharp forms are appealing when you're looking for something aggressive.
On the surface, "consumers" (what I name those seeing the art, but not creating it) will see this as inspiration, or even accuse people of copying, but this is only because they're unaware of the scale of what's going on. Someone sees a cool green helmet and they think it must copy Halo (the only power armor game they play) when in reality there are 100s of artists creating similar helmets simply because they're a good idea, not because they saw someone else do it.
And don't worry, you weren't offensive in the way you worded your initial comment, but I'm very open with educating about this issue, and often the first step is simple: "go look at them again". Once you make yourself aware that things can be similar without copying, you start to notice the originality in things.
Cool piece overall, but I especially love the sexy revolver. Wheel guns are drastically overlooked for their limitations on ammo capacity, but they are infinitely more versatile than automatics for the type of specialty ammo that one can use; and that can often compensate for the lower cartridge count.