is joystick necessary?

[Bounder!]

Get a joystick if you can, preferably one with a twist stick for rudder control. You should be able to pick up a fairly decent joystick for £20-30 and it will make flying a lot easier and more enjoyable. If you have the cash (£30-40), I'd personally recommend looking at the Saitek Cyborg FLY5 Joystick - served me well and has twisty stick, lots of buttons and two leavers which are useful for controlling throttle and propeller pitch.