Why do you want to Lucid Dream?

I want to lucid dream for fun.

You have the freedom to do whatever you like :)

The reason I lucid dream is because of what I see as a great opportunity for experience that would otherwise be unavailable in a more realistic setting. I enjoy the feeling of freedom that comes with the possibilities of the dream worlds. I also like to look at it from a scientific point of view and experiment with consiousness. I make comparisons between real life waking experience and the experiences of dreaming. The potential for creative endeavors is awesome and that is exactly what I'm attempting to tap into.

Why do I want to control my dreams?

Why not? :D

Taking advantage of my sleep time to experience flight, casting fireballs, visiting other planets, summoning creatures/people, walking through walls, getting rid of nightmares etc...

That is one aspect, there are so many more pros and (in my opinion) no cons. It's a phenominon that needs to be explored much, much further!