I don't know if the input lag is fixable, because I'm still not certain how much of it is intended. The game doesn't want you to do anything until an animation finishes out and there's no input buffering. For me, it's noticeably awful in two areas: the radial menu and focus strikes. It's extremely frustrating wanting to quickly switch to flash pods or luring pods only for the radial menu to just deny you for no reason. If you really want to implement those tools in your play, it's generally safer to just have them on your slinger most of the time, which locks you out of the other slinger ammo types. There are so many times I could have prevented a monster from leaving the zone if I could properly switch to either of those items.
And despite wounds being such a big advantage the hunter has, it's pretty difficult to actually land the focus strike sometimes with certain weapons when you have to deal with the inputs dropping on top of the often erratic movements of monsters.
I think the amount of damage Lagi and Steve do is fine though. They've injected some much needed difficulty into the game, and I'm quite satisfied with both.
Ah, yes, the Negotiator:
General Kenobi
<sneaky beeping>