Agree the 384 resolution is pretty versatile. Friend and I both have AGMs - one Rattler, one Adder. We just kill rats and pigeons in/out of dairy barns, but would have zero problem killing deer to 200 yds or so with them. We tried a 256 resolution and weren't happy. Same with the ATN (?300 resolution?).
Also agree the 640 doesn't add much. I have a 50-640. Better? Yes. But not enough better to justify the premium for most my purposes.
I agree for the most part, although there are some scenarios here where a hunter here had better have either 640res or a decent resolution NV setup with good illuminator. This would be when trying to positively identify a target animal in the 175yd+ range, especially in sub-par conditions, tall grass, or the like. I was hunting the other afternoon (daylight) when a black shape stepped out on a narrow lane at 190yds or so. I immediately thought it was a hog, but once it began moving again, I could see that it was a chubby black bear cub. If that cub had been stationary at that range at night, I don't know for sure that your typical 2-2.5x 384res thermal scope would have offered the ability to confidently tell it from a hog. A 640res thermal likely would, and I'm sure that a good digital NV setup would. For folks that are only hunting inside 100yds, that capability might indeed be an unnecessary expense.
