your tank looks lovely!
in response to your question about light - On average most plants will do just fine under 2 watts per gallon however plants such as java moss and java fern will do fine in 1-1.5 watts/gallon. For a really succesful tank 3-4 watts/gallon is needed. However with this high lighting CO2 will need to be injected.
It also depends on the type of bulbs you're using:
Kelvin - this is the colour of the bulb, most aquarists use bulbs between 5000K and 7000K.
CRI (colour rendering index) - how close to natural light the bulb is, any bulb above 85 will be fine.
I found this site really helpful when setting up my planted tank:
http/www.aquahobby.com/articles/e_plant.php