I'm running GNOME 3 on Fedora 25, which uses Wayland as opposed to Xorg. I'm having trouble finding a way to modify my mouse wheel scroll speed and touchpad scroll speed without affecting mouse/touchpad sensitivity and acceleration. My mouse wheel scrolls only one or two lines at a time, which is maddening and way too slow. My touchpad two-finger scrolling is the opposite, it is way too sensitive and I find myself scrolling way past where I want to go. After extensive Googling all I'm left with are ways to modify these settings when using Xorg, but I'm on Wayland using libinput. The GSettings GUI does not have these options separated. Any help would be greatly appreciated.
I've tried Wayland also, and switched back to xorg finally, just because of the touchpad/mouse problem. I'm afraid that xorg may still be the best solution. Libinput just doesn't provide much for touchpad/mouse calibration. This is too bad for laptops on Wayland...
Though may not be of some help, here's some info on libinput.
To switch to xorg on Gnome 3, you can click on the gear button and choose "gnome on xorg" when you're on the login screen.