I really like LEDs - I have gone exclusively to LED lighting for FW and SW applications. T5HOs are good lights as well however.
I prefer black substrate in a planted tank. I think that it will look nice.
When you start your scape, keep the hardscape in odd numbers, and remember the golden ratio and resist the urge to keep things symmetric or centered. Triangular compositions turn out nicely, and keeping the focal point of the hardscape at either 1/3 from the left or right usually leads to a pleasing scape. It is amazing how big a difference those things, though subtle, can make to your final outcome.