Cool. My first thought is to recommend you get a cheap RTF quad to learn on like the Syma X5C1 for example. It can be had for around $50.00 and will save you money in the long run. Replacing parts on a toy quad is really cheap compared to your larger build. You WILL crash in the beginning. A lot.
Building something in the 400 to 500mm range is ideal. It's a great size . It is stable enough to easily lift a camera and still supply spirited performance. I would suggest using material other than aluminum. One, it bends easily in a crash and two, it transfers vibration easily. That will cause problems with your video and can even affect your controller. My favorite material to use for playing around with a design is basswood and Sitka spruce. They make full size airplanes out of this stuff. Very light, incredibly strong and if you crash you can replace an arm in 5 minutes for $.50. Check out these guys for versatility and helpful build tips no matter what material you use;
http://quadlugs.com/
The KK is a great little controller. Perfect to learn on. As you progress and decide you want to do serious video with FPV you can always replace it with something more sophisticated.
Motors, props and ESC's are what keep your quad in the air. MY opinion is that bottom feeding on the cheap Chinese crap out there is a complete waste of time and money. It's like buying used tires for your BMW. For the type of flying you want to do I suggest you look into 2213 or 2216 900kv to 980kv motors. Depending on the final wheelbase of your quad look to get 10", 11" or even 12" props( if you use longer arms). For ESC's I would use 25a or 30a. They will run cooler.
Here is a list of the brands that I use. They have proven to offer excellent performance and value at each price point;
Good is SunnySky motors, ZTW Spider 30A Small ESC's and Castle Creations UBEC. Better is T Motor motors and S series ESC's and Castle UBEC. Best is KDE Direct motors, ESC's and UBEC. Absolute primo and that is reflected in the price. I have only one set on a quad right now and am saving up to purchase another set for my next build.
Don't forget you will need a radio. Again. Get a good one like a Spektrum, Futaba or Taranis. Consider that , like buying good tools, you will have this for a long time and use it for many future models.
Well. That's my opinion. Hope it is of some help to you or at least food for thought. As you get into this hobby I believe you will find it's really a disease!!
Enjoy!!!!
