I would like the gathering fatigue to go, but at the same time, I dont want one area filled with gatherers like crazy, so I don't like the system that much, but I can deal with it being there.

There is a wall that crafters have where suddenly their success rate floors and they're unable to complete synths. This also turns out into a lesser skill gain rate.

I'd like to know if this crafting fatigue type will also go with exp gain fatigue.
What crap do you base that one? I know people who crafted several 100k SP on crafts in a matter of 2-3 days(someone I know grinded ARM from 41 to 47 in 4 days) and his successrate never decreased...he got less SP due to fatigue, that's it. He said his fails increased slightly the higher his fatigue was, but it never hit a "wall" where it was not possible to go on, he still completed synths as much as before.

I personally never grinded more than around 150-200k at once but my successrate never dropped as well...