Peyton,
when you press "X" does auto pilot kick off even if you dont touch the stick?
If this is the case try increasing deadpan on the rudder axis,watch the number readout in map controls and make sure they dont change. You may have to enable scaling and adjust the sliders if the deadpan doesnt stop the numbers from changing.
This is usually caused by spiking in the joystick,the unwanted inputs cause auto pilot to kick off,just like if you pulled on the stick.
as for your gunsight question,I setup the default or home view as my gunsight view and adjust it as needed. If you need to you can zoom from here and adjust that as well. Maybe changing to another type of gunsight might help you out,that can be done in preferences,gunsights. Many players have made all sorts of gunsights,find 1 thats not too cluttered up and practice,practice,practice!

PS: did I mention practice?