1. All FEAR weapons are death at any distance. They all do such insane amounts of damage, there's absolutely no point in using any other gun besides the SMG or occasionally the assault rifle.
2. That little bubble effect has appeared in other games already. And the rest you describe pretty much mirrors every other grenade in every other game ever made.
3. The slow-mo injector makes you go slow when you use it, too.
4. Melee attacks should be cool, you're right. Jump kicks killing people, maybe. Slide kicks that kill in one shot, absolutely absurd. Breaking an ankle should not kill me.
5. The remote and proximity mines are this game's only real redeeming feature. And it isn't enough to redeem the rest.