I think that 1000 W is too big, but only for the space you showed us. I also like the reflector better that you see when you click the "next" button on that page. If you did something like that, you could have 1000 watts. Never tried the buckets. Seems like the roots would stay too wet when they got down close to the water in the bottom. Maybe it would be good too skip veg, and the roots might not have a chance to get down too close to the constant moisture. And rockwool? Bleaaacghhh (sp?) I hate that stuff and it's definitely not for beginners. I wish you extra luck with that shit. You are going to need more than 1 small fan if you are going with HID lighting. Plan to spend as much on ventilation as you do on lighting, or go with fluorescents.

Good luck. Keep us posted.