if you are having trouble fitting possible lights onto the tank with the canopy, you could always skip the canopy and just have the cherry stand. it still looks amazing and you don't have to possibly sacrifice lighting because of the canopy.
as far as WPG go, I wouldn't worry too much about it. In my experience with planted tanks that I have maintained over the years, as long as you have good lighting with good coverage and depth penetration, and you are using good fertilizer/substrate, the WPG rule is not really an issue.
eg. I have grown amazon swords the size of basketballs (that filled an entire 35 gallon) simply with two hagen powerglo standard flourescent strip lights (at only 40W total). However, I was putting root tabs in every other week as well as adding seachem fertilizer each week and they grew like mad.
and they are a higher light plant..