Woah, nice to see yet another competent animator out there.
Your biggest problem seems to be time distribution - while you certainly have control over motion, a lot of the time things are taking way longer than the rest of the animation. You need to make stuff even.
You also seem to have random bits of "popping", where suddenly you've got motion that goes way faster than the rest of the anim or jerks off to a strange direction (ex : mag out for the AR). That needs to go as well.
The pistol anim lacks a certain... character? It's just *slip* *slap* *end*. I always feel that animations should be stylized when possible; don't be afraid to sacrifice a reasonable degree of realism for a bit more artistic flair.
Some of the endings/return to origins look funky too. Work on a setup that works well for you, because the ending can totally ruin an otherwise good animations.
Also get yourself an H2 rig and stop using that horrible h1 setup, christ.
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