Hi and welcome to the forum.
Use of code tags on your very first post is great! Karma++
It is not unexpected to have a servo provide less than 180 degrees. There is a bit of variability, even among different servos of the same model.
Rather than (or in addition to) the joystick value, I would want to see the servo command value servoValX.
The behavior of your second servo is just bonkers. I suspect it is a bad servo and will need replaced.