An arduino with a wireless module is certainly up to this, understanding that you will need some real motor controllers for CIMs. It is also possible, depending on how many user controls you are planning to have, that you can use xBee as your wireless controller. This would let you make a small handheld controller with nothing but an xBEE, a battery, and the actual joysticks and buttons to control the robot. There are several xBee-to-Arduino adapter shields available. This is the basic model we used on our
air cannon, which has four CIM-controlled talons on the drive system and two 3/4" pneumatic solenoid valves controlled from 5V relay modules controlled from an arduino with an xBee shield. We are also planning to add another talon-controlled and potentiometer-steered rotator for the guns next year. The hardware is all there, we just need to write the software.