You are complaining about slow response speed ?
One possibility is that your system is working properly, but your expectation of how it should work, is wrong.
The other possibility is that it is not working properly. If you think it is "slow", or taking too long to respond, you
need to check for operations which your program is doing, which are either inherently time-consuming, or which
are subject to some long delay while they are "waiting" for something, which may or may not be happening.
There is nothing "slow" in the code you have shown us.
What we cannot see, is the code for the roll and pitch objects, on which you are calling functions. Maybe the
person who wrote those functions put a long delay() in them, to allow for the time it takes for the servo to
re-position itself. Who knows ? We don't. We can't see how those objects are implemented.
My previous suggestion was to make those lines a comment, so they don't get executed. Put two slash characters
at the start of the line, and the compiler will ignore it. Like this
// pitch.set(pwm_value); // this line will do nothing
See if loop() runs faster.
The other suggestion, is to see how often loop() actually runs. See how many milliseconds it takes.
If loop() is running in a couple of milliseconds, then your system is not really "slow". If loop() is
taking hundreds of milliseconds, then there is a delay hidden in there, somewhere.