Servo limitations vs SoftwareServo
I'm not sure which SoftwareServo library you are talking about, but with regards to the built in "Servo.h", no, it will not disrupt the arduino's other communication abilities, and they will not disrupt it.

I've used servos simultaneously with Serial, I2C, and SPI before and never had any problems. 

The servo library does use a timer, but it will only conflict with an external library or code that uses the same timer. Which timer it uses depends on the board, just look in libraries/Servo/src/avr/ServoTimers.h to see which it uses, in what order as they fill up. Filling one up takes effort though, by default it puts up to 12 servos on each timer. The processing overhead is very low since they only update at 50Hz, so that will not become a problem.