Been doing both for many years. Both are very addictive sports. Which one I prefer depends on the conditions:
In 20+ kn side shore wind and decent swell it's windsurfing 100% for me, no contest. In windsurfing I feel like I am one unit with the rig and the board. In kiting I am still being towed by something externally (which I can control unlike a boat in wake boarding). No boost in kiting gives me the same buzz as looping over a wave in windsurfing. On a kite in the end you are still suspended by a "parachute". Maybe if I had the skills & guts to do mega kite loops I would feel different?
However, in average Perth metro conditions I have much more fun kiting. I find Windsurfing in choppy water without waves relatively boring, probably since I can't freestyle. Freestyle windsurfing is incredibly hard and tedious to learn. You need less wind to be boosting jumps and doing tricks and riding waves on a kite (unless maybe you're putting a sail on a SUP). You notice the lulls much much less on a kite. On a windsurfer you come off the plane in the lulls, especially on marginal days. This can be very annoying. On a kite you just keep going and barely notice. It's also much easier to ride shore break on a kite since you plane almost instantly and can change direction faster.
So, if you still have the mind and body of a teenager, you are going to move to a windier place than QLD, and you are prepared to put in several days a week for the next couple of years learning a difficult but rewarding new sport (i.e no 8-5 job and your wife and kids have left you

), then give windsurfing a go. Otherwise I would suggest you start with some kiting lessons.