Why does a helicopter need cyclic control rather than just tilting the whole main rotor? Helicopters use a cyclic control to tilt each blade differently through the rotor's revolution. This is quite a complex mechanism. What is the advantage of this vs tilting the whole rotor plane? This seems to be a much more simple solution.
Tilting the rotor doesn't do much, in fact the body will be tilting more than the rotor. The gyroscopic effect will work against you.

The cyclic increases lift on one side of the rotor which will tilt the rotor. Which will then move the craft in the correct direction.

In other words the cyclic system gives a more direct response to input.